This paper proposes Genetic Programming Modeling (GPM) algorithm on chaotic time series.GP is used here to search for appropriate model structures in function space
and Particle Swarm Optimization (PSO) algorithm is introduced for Nonlinear Parameter Estimation (NPE) of dynamic model structures.In addition
GPM integrates the results from Nonlinear Time Series Analysis (NTSA) to adjust the parameters and as the criterion of founded models.The simulation shows the effectiveness of such improvements on modeling chaotic time series.