In order to realize prediction of probability of successful water-exit for underwater vehicles under measured wave action and provide a rapid prediction method of underwater launch for submarine operations, the calculation model of water-exit attitude parameters of the underwater vehicle was established on the basis of the boundary element method. The water-exit attitude parameters of underwater vehicles under different wave conditions were calculated. Meanwhile, the water-exit attitude parameters under different wave conditions were integrated to form a regular wave database. The measured sea conditions in a certain period of time in the Bohai Bay were used as the launch environment, and a wave height probability distribution model conforming to the Rayleigh distribution was established. The pitch angle of the tail touching water was taken as the judging condition to realize the prediction of probability of successful water-exit for underwater vehicles under measured wave action. The calculation results show that, considering the worst conditions, the deviation of the water-exit pitch angle relative to the static water condition decreases with the increase of the wave height; under the same wave height, the deviation of the water-exit pitch angle shows a cosine variation law due to the influence of water-exit phase. The prediction method has certain reference value for submarine combat to determine the launch timing and provides a reference for the successful probability of underwater launch.