Abstract: Tent mapping is extended to double tent mapping, it is proved that integer double tent mapping has uniform distribution characteristics, but due to no significant change in periodicity, an improved integer piecewise tent mapping is proposed. After introducing dynamic parameters and coupled map lattices, the dynamic integer coupled piecewise tent mapping model is completed. The Lyapunov exponent and randomness of the model were analyzed. The mapping is applied to image encryption, adopting pixel scrambling, 3D pixel diffusion and pixel XOR encryption, followed by histogram, adjacent pixel correlation, information entropy, key sensitivity tests. The experimental results show that the proposed algorithm has better encryption performance and security.