Abstract: In order to study the shear resistance of vertical connection in PRC structures under repeated loading, according to the theory of probability and the indeterminacy of material behavior, geometrical parameters and calculating mode of structural element, the authors studied the probability statistic characteristics of the proposed calculation equation of the shear-resistance of PRC structure after the degeneration of perpends. The results show that the strength teserve of the equation is larger than the strength reserve of the collective level of reinforced concrete structure under shearing, up to about 30 percent and its variability is lower than the latter. Therefore, the calculation and design based on the equation are safe and reliable.