Abstract
The proving research of the offshore wind power has been continuing at the offshore of Choshi. The foundation of the offshore wind turbine is the gravity foundation. The wave pressure acting on the foundation of the wind turbine has been measured to examine the validity of the evaluation method of the wave force. The linear relationship between the siginificant wave height and the maximum wave pressure has been revealed by using the observed data, and it has been confirmed that the evaluating method of the probability distribution of the wave pressure is appropriate.