Abstract: Due to the pseudo-randomness of chaotic map and its sensitivity to parameters and initial values, it can enhance the performance of image encryption algorithm. And due to the simple structure and high transmission efficiency of Sine map, it can be widely used in the field of image encryption. In the security application sense, there are some problems in Sine map, i.e. the Lyapunov exponent is too small and the probability density distribution is not uniform. In order to overcome the shortcomings of Sine map in chaotic cipher design, a parameter coupled piecewise sine map (PCPSM) was proposed, and a three-dimensional chaotic model (3DPCPSM) was constructed using PCPSM as the basic unit. Then, a new color image encryption algorithm based on 3DPCPSM was proposed. In the encryption algorithm, two elementary transformation matrices were constructed based on three pseudo-random sequences output from the model, scrambling the RGB information of the color image. And then, an integer sequence was constructed by extracting state values from the model, and the scrambled image was diffused to generate encrypted image. Simulation experiments and performance analysis show that the scheme is safe and reliable, and can effectively meet the needs of secure image transmission in the network.