Based on water wave modeling, alternating ball-pushing modified algorithm is proposed to solve lack of the basic ball-pushing algorithms and some situations on the robotic fish water polo game. According to the classic ball-pushing algorithms and the theory based on water wave modeling, the modified algorithm transform the coordinate system and the robotic fish alternates to push ball and the ball forward in a curved manner. To improve the accuracy of the real-time geometry sites of the ball and reduce errors, the algorithm is optimized through water wave modeling. Results show that this ball-pushing algorithm can improve the efficiency of goals and shorten the goal time.