Abstract: Based on the data of marine fishing production structure in the South China Sea during 2015−2017, we investigated the effect of summer fishing moratorium by studying the indicators such as daily yield, daily output value, catch per unit effort (CPUE) and trawl fishing rate before and after summer fishing moratorium, with differential test and growth rate analysis. Compared with the data before the moratorium, the daily yields of fishing boats after summer fishing moratorium increased by 19.21%, 49.99% and 114.64% in 2015, 2016 and 2017, respectively; the average daily output values increased by 0.40%, 16.06% and 49.14%, respectively; CPUE increased by 7.12%, 73.30% and 110.90%, respectively. The fishing moratorium system had a significant impact on the daily output of fishing vessels (P<0.05), but a limited impact on the daily output value, CPUE, catch rate and fishing structure (P>0.05). To sum up, summer fishing moratorium in the South China Sea affects the yield increment significantly, but affects the resource community structure not so much. The effect in 2017 is better than that in 2015 and 2016.