Artificial concrete blocks are used for the armor layer of breakwater, withstanding rough sea, with the characteristics of good stability and easily installment. The double-link armor block is a new type one, which is adopted in a breakwater repairing engineering of power station. One scale 1∶30 physical model is performed in the wave flume, and the cross section with the double-link armor block is verified in stability under different water levels and wave conditions. The breakwater is mound sloping breakwater, armored by 8 t double-link armor block. The wave is above 5 m in prototype, and the average wave period is 13.83 s. A stable section is obtained by testing. The parameters of double-link armor block are obtained as coefficient of stability KD, form factor c, porosity of blocks P′, roughness parameter of permeation KΔ and block number in 100 m2 N. It is shown that the double-link armor block has advantages including economizing material as one layer, random placing, easy manufacturing, as well as high stability, etc. The achievements of design and study have been applied to the engineering and achieved favorable effects. The double-link armor block is very worthy of popularizing.