Abstract: Based on the catch records of YUE DIAN YUNO. 42212from August 2012 to June 2014, we studied the catch composition and fishing season by steel light falling-net fishing vessels in the South China Sea. The results show that Sthenoteuthis oualaniensis, Carangidae, Scombrid, Loliginidae and Trichiurus japonicas were the main catch species, accounting for 69.8%, 12.6%, 7.3%, 3.9% and 3.5% of the total catch, respectively. The fishing ground could be divided into continental shelf waters and deep waters of high seas. Main catch species in shelf waters were Carangidae, Loliginidae, Trichiurus japonicas and Scombrida; the main catch species in deep waters was Sthenoteuthis oualaniensis, which was less diverse. The fishing season in shelf waters was from August to February in the next year ( 1～20 fishing days per month and 10 d averagely; the average catch per day in one month was 370.5～3 670 kgd-1 and 1 152.0 kgd-1 averagely) . The fishing season in deep waters was from February to June ( 1～30 fishing days per month and 13 d averagely; the average catch per day in one month was 1 000.0～10 190.0 kgd-1 and 4 071.3 kgd-1 averagely). Since the fishing operation in deep waters had higher productivity and more total catch than those in shelf waters, it is necessary to develop steel light falling-net fishing vessels to explore the fishery resources in deep waters of high seas.