Abstract: According to the light-seiners vessels data and oceanographic environmental data sea surface temperature (SST), sea surface height (SSH) in the northwest Pacific from May to October, 2015, we analyzed the potential habitat of Scomber japonicus using maximum entropy model (MaxEnt). Besides, compared with the actual operation location, we studied the relationship between the oceanographic environmental factors and monthly distribution difference. The results found a nearly same trend between the actual catch positions and change of the potential distribution areas. On the longitude direction, the changes were significant in June and September, mainly concentrating in 147.5°E–152.5°E and fluctuating in direction of west–east–west. On the latitude direction, the potential distribution area mainly concentrated in 40°N–42°N. The Jackknife test indicats that SST is the most important oceanographic environmental factor which influences the distribution of S.japonicus. The convergence of maximum and minimum values of SSH also affect its distribution. The changes of SST and SSH are the main causes of the potential habitat distribution and difference of S.japonicus in the northwest Pacific Ocean.