Abstract: In order to choose the best laser parameters and the photovoltaic cells (PV cells) parameters to reach a high power conversion efficiency (PCE) of the laser wireless power transmission (LWPT) system, we experimentally studied the output characteristics of the receiving system, the PV cells, under laser irradiation. The GaAs and Si PV cells were irradiated by laser with wavelengths of 808 nm and 915 nm, and the output characteristics and PCE of the PV cells under different conditions were analyzed. These conditions include: laser power intensity, laser incidence angle, temperature and material of the PV cells. In the experiment, when 808 nm laser power intensity increased from 0.06 W/cm² to 0.37 W/cm², the maximum output power of Si PV cell increased from 0.12 W to 0.32 W, but its PCE decreased from 50.9% to 21.2%; the maximum output power of GaAs PV cell increased from 0.40 W to 1.07 W, but its PCE decreased from 57.9% to 23.8%. The experimental results show that with the increase of laser power density, the output power of PV cells increases at first and then tends to be stable, but the temperature rise caused by high power intensity laser will lead to the decrease of power conversion efficiency of PV cells. So, the selection of laser power intensity and the temperature control of PV cells are keys to increase the PCE of LWPT system.