Abstract: The correlation between the temperature of seawater and fishing grounds is studied in detail, the general conclusions reached can be expressed as follows: 1.In the course of spawning and overwintering migration, the formation or the dispersion of fish shoals, patterns of fish behaviour and the breadth of migration route are influenced by the horizontal temperature gradieni.When the optimum temperature isotherm diverges from inshore or offshore waters,the migration route diverges as well.