Abstract: The distribution of strength matching coefficient for 10Ni5CrMoV steel welded joint had been investigated by using the Monte Carlo method and the sorting method of equalmatching form had been put forward.The result shows that the equalmatching characteristic of 10Ni5CrMoV steel welded joint is prominent.The probability of equalmatching is 48.11%,as well as,that of undermatching and overmatching are 47.55% and 4.34%,respectively.The mean-value of strength matching coefficient is nearly higher than its lower limit,which is 0.955.Moreover,the strength standard deviation of the base metal is higher,which is about 54% more than that of weld metal,which is the main reason that the strength matching coefficient standard deviation is fairly higher.Furthermore,the probability is up to 2.96%,where strength matching coefficient is lower than 0.86,it may also be the main reason that the cold crack appears in welded joint.