The purpose of this study was to make the sea with rending of ocean by using the proper algorithm for an emotional online game. We used statistical model to make the sea in this study. In measuring the wave height, we used Fast Fourier Transformation (FFT) to calculate the sum of amplitude and phrase quickly with random numbers of the time. We eliminated the overlap functions of sine and cosines by using the repeatability of trigonometric function. We saved the values of trigonometric function in memory space. Therefore, we could deal with the repetitive calculations by memory access because the same values are repeated in the standard based on π within one cycle of 2π in sine and cosine functions. By changing the sampling size of Windows function, we calculated the mobility on each local area and we applied this mobility to this study according to hierarchical structure. In addition, we used the reflectivity differently by putting the value of k,r into the effect Fresnel reflection. The reason why we used this method was to make the sea look more realistic. In the aspect of the intensity of light of the sea, we did not calculate it and we applied KD- Tree data structure on the density of the values occurred at the time of the sea was created. The advantage of this method was to reduce search time effectively. In this Tree structure, index time log , search time and log time are spend, which is applied to the photon closed to . In the case of KD-Tree, this is a very effective way in saving and recovering. One weakness was that we had to limit the effect of indirect illumination to express a wide sea. However, by using photon mapping, we solved this problem