The paper presents the results of field observation on the ecology and burrow of eleven species of crabs (Crustacea: Brachyura) found on the Cangkou mud beach and Shazikou sand beaches, carried out in the period from May, 1963 to November 1964. The morphology of their burrows as well as the environmental factors influencing the form of their burrows such as temperature, salinity, etc., are deseribed.