In recent years, in the process of designing breakwaters for some large deepwater ports, it is found that armor blocks, which are between the design wave heights of 1-1.5 times below the outside design low water level, cannot always meet the stability requirements in the physical model tests when according to the current standards to determine its stable weight. It needs to increase the weight of the blocks，but the suitable number of blocks can only be decided through physical model tests and there is not a clear standard as the basis of design. Aiming at this problem，this paper studies accropodes and dolosses through the systematic physical model test have got the block stability coefficient in critical stable state and recommends calculated values for the designs.