Shielding is a common measure for the radiation protection. In the design process, radiation shielding calculation using computer codes is employed to achieve the proper shielding plan. MCNP and DORT are common programs used for computing radiation shielding. Based on different principles and algorithms, each of these programs has its own defect at certain areas. Achieving MCNP and DORT coupling is taken aim at, by studying the functions and features of MCNP and DORT, and the interface code is programmed. The method for converting data between MCNP and DORT is realized, Coupling between MCNP and DORT is achieved. So that the application scope of these two programs is able to be enlarged. After the validation, the conclusion is drawn that the interface code is able to convert the input and output files of MCNP and DORT successfully. Both accuracy and efficiency for coupling calculation are acceptable, having quite good management ability for all kinds of problems. The coupling method has been applied to technical problems and would be further validated by the feedback data.