Fractional order differential algebraic equations (FDAEs) are more complex than fractional differential equations (FDEs) on analytical and numerical analysis. In this paper, the sliding mode control theory is introduced to convert the FDAEs into FDEs firstly. Then the predictor-corrector method is used to solve FDEs. To avoid the constraint violations, the numerical results have been corrected. Furthermore, the iterative convergence of numerical algorithm and stability are discussed in detail. Finally, a numerical example is given to verify the validity of the proposed approach.