Crocodile shark, Pseudocarcharias kamoharai, is a common by catch species of tuna longliner. As an important part of the oceanic food chain, it plays a vital role in the marine ecosystem. According to the total of 383 crocodile shark samples collected by China’s national tuna fisheries observers in the tropical Eastern central Atlantic Ocean (4.24°-14.03°N，27.13°-38.28°W), the biological characteristics of both females and males of crocodile sharks were analyzed and described, respectively. The results can be summarized as follows: (1) The female male ratio was 1:0.36, and with significant difference; (2) The dominant fork length of males and females was 75-95 cm，65-90 cm, respectively; (3) There was no significant difference between Hepatosomatic indices (HSI ) and gonad development for male of P. kamohara, however, HSI of mature individuals was greater than that of immature individuals of female; (4)96.8% of males and 56.12% of females were mature. Maturity stages at Ⅱand Ⅳof females’ gonads were dominant and the size at 50% maturity (L50) of female was 84.6 cm in fork length; (4) Feeding stage 0 was dominant with the percentage of 52.38%, and feeding stage 1 accounted for the percentage of 33.86%; (5) The prey composition in the stomachs of these shark samples was mainly sardine (72.56%) and squid (27.44%); (6) The relationships between fork length and round weight for females and males was described by WR=2×10-5LF2.7614, WR=2×10-6LF3.3287 respectively. Due to the difficulty for collecting the oceanic species samples, this study contributed to a better understanding of crocodile shark in biological characteristics, and the information from this study would be helpful for some regional fisheries management organizations to conduct stock assessment and decision making.