Global climate change has a profound impact on the world fisheries. Recently, the composition of catch in Northeast Atlantic Ocean has changed significantly. Based on the catch data in the Northeast Atlantic Ocean from 1982 to 2016 provided by the United Nations Food and Agricuture Organization, the diversity of catch, mean trophic level and the variation of principal component were analyzed in time series. Finally, combined with climate and environmental factors (sea surface temperature, SST; sea surface salinity, SSS; sea surface height, SSH; Sea Ice Concentration, SIC; North Atlantic Oscillation, NAO; Arctic Oscillation, AO; Atlantic Multidecadal Oscillation, AMO) in the Northeast Atlantic Ocean, the relationship between catches composition and climate change was explored by generalized additive model (GAM). The results showed that the diversity generally presented a declining trend, it was at a relatively low level during 2002 to 2010. The mean trophic level decreased slowly before 2002, then began to rise sharply. The correlation analysis showed that the changes of these two indicators were related to the environmental factors. The principal component analysis of catch composition showed that the variance of the first principal component was 35.3%, and it also has a close relationship with climatic and environmental factors, which could characterize the change of catch structure under the influence of climate. The results of GAM analysis showed that the orders of the contribution to structure change of catches were in sequence of SST, SSH, SSS, SIC and NAO.