A class of modeling and control combination method is proposed to realize the speed adjustment of robotic fish with multi-joint caudal fin. Targeting at controllability, a swing rule and propulsion speed performance reference(SSPR) model is established based on an energy conversion coefficient, and the efficiency is converged to a controllable and adjustable range by system’s known parameters. Then, an adaptive iterative learning control policy is designed to match the SSPR model, the control system can identify and update the energy conversion coefficient timely and periodically, and realize the speed self-adjustment of robotic fish in a strange water environment. Simulation analysis verifies the correctness of the model and control method.