This practical method for calculating the probability of a wave breaking and the distribution of breaking weve heights is based on the joint probebility distribution of wave heights and periods derived by Sun Fu and the breaking criterion obtained by Ochi and Tsai from measurements of irregular waves generated in a tank. Computations for differnt an states using the P-M spectrum and the JONSWAP spectrum showed that the probability of wave basking (or the distribution of beding were heights) in the deep ocean can be determined, at least approximated, from the zero, the first and the scond moments of the wave spectrum. This practical method for calculating the probability of a wave breaking and the distribution of breaking weve heights is based on the joint probebility distribution of wave heights and periods derived by Sun Fu and the breaking criterion obtained by Ochi and Tsai from measurements of irregular waves generated in a tank. Computations for differnt an states using the PM spectrum and the JONSWAP spectrum showed that the probability of wave basking (or the distribution of beding were heights) in the deep ocean can be determined, at least approximated, from the zero, the first and the scond moments of the wave spectrum.