Based on the LINAC of BEPCII, a high-polarized, high bightness, energy-tunable, monoenergetic laser compton backscattering (LCS) gamma-ray source is under construction at IHEP. The gamma-ray energy range is from 1 MeV to 111 MeV. It is a powerful and hopeful research platform to reveal the underlying physics of the nuclear, the basic particles and the vacuum or to check the exist basic physical models, quantum electrodynamic (QED) theories. In the platform, a 1.064 mm Nd:YAG laser system and a 10.6 mm CO2 laser system are employed. All the trigger signals to the laser system and the electron control system are from the only reference clock at the very beginning of the LINAC to make sure the temporal synchronization. Two optical transition radiation (OTR) targets and two charged-couple devices (CCD) are used to monitor and to align the electron beam and the laser beam. With the LCS gamma-ray source, it is proposed to experimentally check the gamma-ray calibrations, the photon-nuclear physics, nuclear astrophysics and some basic QED phenomena.