In this paper, a new fractional Riccati equation rational expansion method is proposed to establish new exact solutions for fractional differential equations. For illustrating the validity of this metho d, we apply it to the nonlinear fractional Sharma-Tasso- Olever (STO) equation, the nonlinear time fractional biological population model and the nonlinear fractional foam drainage equation. Compared with the existing results in the literature, more exact solutions are o btained by the proposed method. We also illustrate the application of the established exact solutions.