A 3D statistical channels model for mobile frequency selective fading MIMO channels was proposed and a new joint space-time-frequency correlation function was derived. The 3D channels model integrates many known channel models and the new space-time-frequency correlation function takes into account such parameters of MIMO system as the Doppler spread, the 3D angle spread, and antenna array configuration. Furthermore, the impact of nonuniform angle spread and antenna array configuration on the Cross-correlation Performance of channels were analyzed based on the new correlation function.