PAGE 1
000 A000000 10/31/2010
000 C000000 1388126
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 6.1
000 J000000 A
001 A000000 PIONEER DIVERSIFIED HIGH INCOME TRUST
001 B000000 811-22014
001 C000000 6177427825
002 A000000 60 STATE STREET
002 B000000 BOSTON
002 C000000 MA
002 D010000 02109
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 N
007 B000000 0
007 C010100 1
007 C010200 2
007 C010300 3
007 C010400 4
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
008 A000001 PIONEER INVESTMENT MANAGEMENT, INC.
008 B000001 A
008 C000001 801-8255
008 D010001 BOSTON
008 D020001 MA
008 D030001 02109
008 A000002 MONTPELIER CAPITAL ADVISORS, LTD.
008 B000002 S
008 C000002 801-00000
008 D010002 BERMUDA
008 D050002 BERMUDA
010 A000001 PIONEER INVESTMENT MANAGEMENT, INC.
010 B000001 801-8255
010 C010001 BOSTON
010 C020001 MA
010 C030001 02109
010 A000002 STATE STREET BANK & TRUST COMPANY, LLC
010 C010002 BOSTON
010 C020002 MA
PAGE 2
010 C030002 02101
011 A000001 MERRILL LYNCH & CO.
011 B000001 8-7221
011 C010001 NEW YORK
011 C020001 NY
011 C030001 10281
011 C040001 1201
011 A000002 UBS INVESTMENT BANK
011 B000002 8-000000
011 C010002 XX
011 C020002 CT
011 C030002 00000
011 A000003 RBC CAPITAL MARKETS CORP.
011 B000003 8-045411
011 C010003 MINNEAPOLIS
011 C020003 MN
011 C030003 55402
011 C040003 4422
011 A000004 ROBERT W. BAIRD & CO.
011 B000004 8-00000
011 C010004 MILWAUKEE
011 C020004 WI
011 C030004 00000
011 A000005 JANNEY MONTGOMERY SCOTT, LLC
011 B000005 8-462
011 C010005 PHILADELPHIA
011 C020005 PA
011 C030005 19103
011 C040005 1675
011 A000006 FERRIS, BAKER WATTS, INC.
011 B000006 8-00000
011 C010006 WASHINGTON
011 C020006 DC
011 C030006 00000
011 A000007 MORGAN KEEGAN & CO., INC.
011 B000007 8-000000
011 C010007 MEMPHIS
011 C020007 TN
011 C030007 00000
012 A000001 PIONEER INVEST. MGT. SHAREHOLDER SVCS., INC.
012 B000001 85-1359
012 C010001 BOSTON
012 C020001 MA
012 C030001 02109
012 A000002 AMERICAN STOCK TRANSFER & TRUST CO.
012 B000002 85-00000
012 C010002 BROOKLYN
012 C020002 NY
012 C030002 11219
013 A000001 ERNST & YOUNG LLP
013 B010001 BOSTON
PAGE 3
013 B020001 MA
013 B030001 02116
015 A000001 BROWN BROTHERS HARRIMAN & CO.
015 B000001 C
015 C010001 BOSTON
015 C020001 MA
015 C030001 02109
015 E010001 X
015 A000002 BANK AUSTRIA
015 B000002 S
015 C010002 VIENNA
015 D010002 AUSTRIA
015 E040002 X
015 A000003 BANQUE BRUXELLES LAMBERT
015 B000003 S
015 C010003 BRUSSELS
015 D010003 BELGIUM
015 E040003 X
015 A000004 BANK OF BOSTON
015 B000004 S
015 C010004 SAO PAULO
015 D010004 BRAZIL
015 E040004 X
015 A000005 NATIONAL AUSTRALIA BANK
015 B000005 S
015 C010005 MELBOURNE
015 D010005 AUSTRALIA
015 E040005 X
015 A000006 ROYAL BANK OF CANADA
015 B000006 S
015 C010006 TORONTO
015 D010006 CANADA
015 E040006 X
015 A000007 DEN DANSKE BANK
015 B000007 S
015 C010007 COPENHAGEN
015 D010007 DENMARK
015 E040007 X
015 A000008 MERITA BANK
015 B000008 S
015 C010008 HELSINKI
015 D010008 FINLAND
015 E040008 X
015 A000009 BANQUE PARIBAS
015 B000009 S
015 C010009 PARIS
015 D010009 FRANCE
015 E040009 X
015 A000010 DRESDNER BANK
015 B000010 S
015 C010010 FRANKFURT
PAGE 4
015 D010010 GERMANY
015 E040010 X
015 A000011 CITIBANK, N.A.
015 B000011 S
015 C010011 ATHENS
015 D010011 GREECE
015 E040011 X
015 A000012 STANDARD CHARTERED BANK
015 B000012 S
015 C010012 HONG KONG
015 D010012 HONG KONG
015 E040012 X
015 A000013 CITIBANK, N.A.
015 B000013 S
015 C010013 MUMBAI
015 D010013 INDIA
015 E040013 X
015 A000014 BANCA COMMERCIALE ITALIANA
015 B000014 S
015 C010014 MILAN
015 D010014 ITALY
015 E040014 X
015 A000015 THE SUMITOMO BANK, LIMITED
015 B000015 S
015 C010015 TOKYO
015 D010015 JAPAN
015 E040015 X
015 A000016 CITIBANK, N.A.
015 B000016 S
015 C010016 SEOUL
015 D010016 SOUTH KOREA
015 E040016 X
015 A000017 HONK KONG BANK MALAYSIA
015 B000017 S
015 C010017 KUALA LUMPUR
015 D010017 MALAYSIA
015 E040017 X
015 A000018 CITIBANK, N.A.
015 B000018 S
015 C010018 MEXICO CITY
015 D010018 MEXICO
015 E040018 X
015 A000019 MEESPIERSON
015 B000019 S
015 C010019 AMSTERDAM
015 D010019 NETHERLANDS
015 E040019 X
015 A000020 NATIONAL NOMINEES LIMITED
015 B000020 S
015 C010020 AUCKLAND
015 D010020 NEW ZEALAND
PAGE 5
015 E040020 X
015 A000021 DEN NORSE BANK
015 B000021 S
015 C010021 OSLO
015 D010021 NORWAY
015 E040021 X
015 A000022 CITIBANK, N.A.
015 B000022 S
015 C010022 WARSAW
015 D010022 POLAND
015 E040022 X
015 A000023 BANCO COMERCIAL PORTUGUESE SA
015 B000023 S
015 C010023 LISBON
015 D010023 PORTUGAL
015 E040023 X
015 A000024 STANDARD CHARTERED BANK
015 B000024 S
015 C010024 SINGAPORE
015 D010024 SINGAPORE
015 E040024 X
015 A000025 BANCO DE SANTANDER
015 B000025 S
015 C010025 MADRID
015 D010025 SPAIN
015 E040025 X
015 A000026 SKANDINAVISKA ENSKILDA BANKEN
015 B000026 S
015 C010026 STOCKHOLM
015 D010026 SWEDEN
015 E040026 X
015 A000027 UNION BANK OF SWITZERLAND AG
015 B000027 S
015 C010027 ZURICH
015 D010027 SWITZERLAND
015 E040027 X
015 A000028 CENTRAL TRUST OF CHINA
015 B000028 S
015 C010028 TAIPEI
015 D010028 TAIWAN
015 E040028 X
015 A000029 HONG KONG AND SHANGHAI BANKING CORPORATION
015 B000029 S
015 C010029 BANGKOK
015 D010029 THAILAND
015 E040029 X
015 A000030 MIDLAND BANK
015 B000030 S
015 C010030 LONDON
015 D010030 UNITED KINGDOM
015 E040030 X
PAGE 6
015 A000031 FIRST NATIONAL BANK OF SOUTH AFRICA
015 B000031 S
015 C010031 JOHANNESBURG
015 D010031 SOUTH AFRICA
015 E040031 X
018 000000 Y
019 A000000 Y
019 B000000 57
019 C000000 PIONEERFDS
020 A000001 LIQUIDNET, INC.
020 B000001 13-4095933
020 C000001 0
020 A000002 ITG INC.
020 B000002 95-4339369
020 C000002 0
020 A000003 SUSQUEHANNA FINANCIAL GROUP, LLLP
020 C000003 0
020 A000004 DEUTSCHE BANK SECURITIES INC.
020 B000004 13-2730828
020 C000004 0
020 A000005 BB&T INVESTMENT SERVICES, INC.
020 C000005 0
020 A000006 UBS SECURITIES LLC
020 B000006 13-3873456
020 C000006 0
020 A000007 JEFFERIES & COMPANY, INC.
020 B000007 95-2622900
020 C000007 0
020 A000008 OPPENHEIMER & CO. INC.
020 C000008 0
020 A000009 CANTOR FITZGERALD & CO.
020 B000009 13-3680184
020 C000009 0
020 A000010 NOMURA SECURITIES INTERNATIONAL, INC.
020 B000010 13-2642206
020 C000010 0
021 000000 0
022 A000001 BROWN BROTHERS HARRIMAN & CO.
022 B000001 13-4973745
022 C000001 208600
022 D000001 0
022 A000002 BNP PARIBAS SECURITIES CORP.
022 B000002 13-3235334
022 C000002 86460
022 D000002 0
022 A000003 SG AMERICAS SECURITIES, LLC
022 B000003 13-3606844
022 C000003 40020
022 D000003 0
022 A000004 BARCLAYS CAPITAL INC.
022 C000004 15325
PAGE 7
022 D000004 0
022 A000005 BANC OF AMERICA SECURITIES LLC
022 B000005 56-2058405
022 C000005 10057
022 D000005 508
022 A000006 J.P. MORGAN SECURITIES INC.
022 B000006 13-3299429
022 C000006 7477
022 D000006 2618
022 A000007 DEUTSCHE BANK SECURITIES INC.
022 B000007 13-2730828
022 C000007 4324
022 D000007 2186
022 A000008 GOLDMAN, SACHS & CO.
022 B000008 13-5108880
022 C000008 4748
022 D000008 870
022 A000009 CREDIT SUISSE SECURITIES (USA) L.L.C.
022 B000009 13-5659485
022 C000009 3920
022 D000009 1623
022 A000010 CITIGROUP GLOBAL MARKETS, INC.
022 B000010 11-2418191
022 C000010 2155
022 D000010 1465
023 C000000 389397
023 D000000 17232
024 000000 Y
025 A000001 BANK OF AMERICA CORP.
025 C000001 E
025 D000001 445
025 A000002 DEUTSCHE BANK SECURITIES, INC.
025 C000002 D
025 D000002 390
025 A000003 GOLDMAN, SACHS CAPITAL II
025 C000003 D
025 D000003 386
025 D000004 0
025 D000005 0
025 D000006 0
025 D000007 0
025 D000008 0
026 A000000 N
026 B000000 Y
026 C000000 N
026 D000000 Y
026 E000000 N
026 F000000 N
026 G010000 N
026 G020000 N
026 H000000 N
PAGE 8
027 000000 N
045 000000 Y
046 000000 N
047 000000 Y
048 000000 0.850
048 A010000 0
048 A020000 0.000
048 B010000 0
048 B020000 0.000
048 C010000 0
048 C020000 0.000
048 D010000 0
048 D020000 0.000
048 E010000 0
048 E020000 0.000
048 F010000 0
048 F020000 0.000
048 G010000 0
048 G020000 0.000
048 H010000 0
048 H020000 0.000
048 I010000 0
048 I020000 0.000
048 J010000 0
048 J020000 0.000
048 K010000 0
048 K020000 0.000
049 000000 N
050 000000 N
051 000000 N
052 000000 N
053 A000000 Y
053 B000000 Y
053 C000000 N
054 A000000 Y
054 B000000 Y
054 C000000 Y
054 D000000 N
054 E000000 N
054 F000000 N
054 G000000 N
054 H000000 Y
054 I000000 N
054 J000000 Y
054 K000000 N
054 L000000 N
054 M000000 Y
054 N000000 N
054 O000000 N
055 A000000 N
055 B000000 Y
PAGE 9
056 000000 Y
057 000000 N
058 A000000 N
059 000000 Y
060 A000000 Y
060 B000000 Y
061 000000 0
062 A000000 Y
062 B000000 0.0
062 C000000 0.0
062 D000000 0.9
062 E000000 0.0
062 F000000 1.1
062 G000000 0.0
062 H000000 0.0
062 I000000 1.8
062 J000000 0.0
062 K000000 0.0
062 L000000 0.3
062 M000000 0.0
062 N000000 0.0
062 O000000 0.0
062 P000000 97.1
062 Q000000 36.5
062 R000000 1.0
063 A000000 0
063 B000000 4.3
064 A000000 N
064 B000000 Y
065 000000 N
066 A000000 N
067 000000 N
068 A000000 N
068 B000000 N
069 000000 N
070 A010000 Y
070 A020000 N
070 B010000 Y
070 B020000 N
070 C010000 Y
070 C020000 N
070 D010000 Y
070 D020000 N
070 E010000 Y
070 E020000 N
070 F010000 Y
070 F020000 N
070 G010000 Y
070 G020000 N
070 H010000 Y
070 H020000 N
PAGE 10
070 I010000 N
070 I020000 N
070 J010000 Y
070 J020000 Y
070 K010000 Y
070 K020000 Y
070 L010000 Y
070 L020000 Y
070 M010000 Y
070 M020000 Y
070 N010000 Y
070 N020000 Y
070 O010000 Y
070 O020000 Y
070 P010000 N
070 P020000 N
070 Q010000 N
070 Q020000 N
070 R010000 N
070 R020000 N
071 A000000 33274
071 B000000 20465
071 C000000 223279
071 D000000 9
072 A000000 6
072 B000000 9918
072 C000000 22
072 D000000 0
072 E000000 114
072 F000000 1002
072 G000000 91
072 H000000 0
072 I000000 6
072 J000000 16
072 K000000 0
072 L000000 16
072 M000000 4
072 N000000 8
072 O000000 0
072 P000000 485
072 Q000000 0
072 R000000 24
072 S000000 27
072 T000000 0
072 U000000 0
072 V000000 0
072 W000000 139
072 X000000 1818
072 Y000000 28
072 Z000000 8264
072AA000000 0
PAGE 11
072BB000000 727
072CC010000 3956
072CC020000 0
072DD010000 7878
072DD020000 0
072EE000000 0
073 A010000 0.9600
073 A020000 0.0000
073 B000000 0.0000
073 C000000 0.0400
074 A000000 725
074 B000000 0
074 C000000 6994
074 D000000 226302
074 E000000 445
074 F000000 1237
074 G000000 0
074 H000000 0
074 I000000 1006
074 J000000 5171
074 K000000 0
074 L000000 3905
074 M000000 31
074 N000000 245816
074 O000000 3088
074 P000000 188
074 Q000000 66000
074 R010000 0
074 R020000 0
074 R030000 0
074 R040000 7154
074 S000000 0
074 T000000 169386
074 U010000 8220
074 U020000 0
074 V010000 20.61
074 V020000 0.00
074 W000000 0.0000
074 X000000 5826
074 Y000000 0
075 A000000 0
075 B000000 161035
076 000000 20.78
077 A000000 N
078 000000 N
080 A000000 ICI MUTUAL INSURANCE CO.
080 C000000 45000
081 A000000 Y
081 B000000 57
082 A000000 N
082 B000000 0
PAGE 12
083 A000000 N
083 B000000 0
084 A000000 N
084 B000000 0
085 A000000 Y
085 B000000 N
086 A010000 21
086 A020000 490
086 B010000 0
086 B020000 0
086 C010000 0
086 C020000 0
086 D010000 0
086 D020000 0
086 E010000 0
086 E020000 0
086 F010000 0
086 F020000 0
087 A010000 COMMON STOCK
087 A020000 723653101
087 A030000 HNW
088 A000000 N
088 B000000 N
088 C000000 N
088 D000000 N
SIGNATURE MARK E. BRADLEY
TITLE TREASURER