A multi-path F-P interferometric system is designed which is used to obtain the multidirectional interferograms of a three-dimensional refractive index field by the computer simulation. The results show that if the sine reconstructed algorithm is used to reconstruct the-three-dimensional refractive index field, a precision of 2. 24 per cent can be reached with 6 F-P interferograms. As an example of application, this system is used to obtain multidirectional interferograms of a three-peak temperature field. The distribution of the three-dimensional refractive index is reconstructed.