Computational ghost imaging (CGI) allows us to reconstruct images under a low signal-to-noise-ratio condition. However, CGI cannot retrieve phase information; it is unsuitable for observation of transparent objects such as living cells. A phase imaging method with CGI architecture is proposed. The proposed method realizes phase imaging with a simple optical setup by introducing pupil modulation differential phase contrast (PMDPC) to CGI. In PMDPC, phase information can be obtained from intensity distributions, which have phase gradient information, and its optical setup is similar to that of CGI. Therefore, the two methods are highly compatible, and the introduction of PMDPC to CGI can be easily achieved. Numerical simulation and an optical experiment demonstrated the feasibility of the proposed method.