A Photon-ion coincidence system for projectile X-ray emission in ion-atom collisions in HIRFL-CSRe internal target is constructed.The system consists of X-ray detectors,ion detectors,signal process electronics and data acquisition(DAQ)system.The photon detector which used for detecting the low energy X-rays are combined with HpGe,Si(Li),Silicon drift detector(SDD)and crystal spectrometer(CS).The ion detectors which used to measure charged-particle trajectories are multi-wire proportional chamber(MWPC).The main purpose of the signal process electronics which using standard NIM electronics is converting the analogue signals from the photon and ion detectors into a format suitable for physics analysis.The DAQ system is based on VME bus and the maximum integrated data acquisition system(MIDAS)developed at Paul Scherrer Institute in Switzerland and TRIUMF in Canada.