A method is given in this paper using incoherent light to realize 2-D complex discrete Fourier transform (DFT). A multi-imaging system is set up, which fully uses the inherent property of optical parallel processing, and 2-D input data can be processed simultanously. A complex can be optically expressed by two encoding methods. 2-D input data of N = 6 is chosen to verify the method. The experimental results accord with the simulant results of computer.