Abstract: According to the theory of complex extreme distribution, the extreme wind speed which recurs once every several years over the sea is estimated. The calculation is supported with the method of binomial log-normal distributioin based on the short-term observations of maximum wind. The estimated value is considered as the basic value and calculations with the empirical for mula incorparating the long-term observations of the maximum coastal wind is taken as the corrected value. The recurrent wind speed for engineering design over the sea is derived by summing up the basic value and corrected one. The result of estimation is approximately equal to those with the Person Ⅲ distribution and Poisson-Gumbel distribution and shows the greater stability than that derived from the binomial log-normal distribution. This method is more significant in estimating the extreme wind speed when the long-term observations are deficient