Abstract: The survey on ecological environment and squid resources was carried out in the fishing ground of Ommastrephes batrami in the North Pacific Ocean( 152bE- 171bW, 39b- 42bN) from June to August, 2001. The results showed that average biomass of zooplankton was 92. 12mg#m- 3( 0. 81- 1035. 68 mg#m- 3) in the all water area, 113. 51mg#m- 3 in the middle water area ( 160b- 180bE, 39b- 42bN) and west longitude water area ( 170b- 178bW, 40b- 41bN) and 22. 89mg#m - 3 in the west water area ( 152b- 157bE, 41b- 43bN) ; the zooplankton abundance was mainly composed of Copepoda ( 42. 11% ) , followed by Thaliacea ( 30. 91%) ; Eucalanus pseudattenuatus, Calanus pacif ica and Dolioletta gegenbauri were main dominant species. Crustacean distribution also corresponded well with the f ishing ground, the centre of which was just located in or near the high abundance area of crustacean ( 50- 100 ind#m- 3) and high biomass area of zooplankton ( 250- 500mg# m- 3) . The distribution of Cephalopoda larva is also in or near the high abundance area of Euphausiacea and Amphipoda.