Water resources system is complicated nonlinear systems in Henan plain, that is operated by nature-man duality driving force and divided into 4 subsystems: precipitate water, surface water, shallow groundwater, and deep underground water. The analysis principle of dynamics characteristics and modeling of water resources system is given and the nonlinear dynamics characteristics of water resources is discussed from fractal character, complexity and evolution types, so the measurement of dynamics characteristics are brought forward, they are Hurst Exponent, Kolmogorov entropy, Lyapunov Exponent, correlation dimension. Fractal character, complexity and evolution types of water resources are given in Henan plain. In this system, there are obvious fractal structure and Chaos character and singular attractor. In the subsystems, precipitate water subsystem is the most complex, surface water subsystem is more complex and shallow groundwater subsystem is relatively simple. This is in line with the actual water system.