In order to solve the problem of low maturity of in-situ lunar resource development technology, a new method of high power laser pyrolysis of ferric oxide under vacuum conditions was proposed. We used high power continuous laser irradiation of Fe2O3 and conducted theoretical calculations and experimental studies on the thermochemical and physical processes of ferric oxide components that may exist in lunar soil during laser irradiation. The experimental results show that: Fe2O3 pyrolysis deoxidization was successful, and there was a directly proportional tendency of laser density and deoxidization efficiency. The highest deoxidization rate was observed under a laser power density of 7.08 kW/cm2 and 30 s irradiation time. The main pyrolysis products were Fe (81.6%), Fe3O4 (7.4%), Fe2O3 (2.9%) and a small amount of Cu-Fe, W-Fe compounds (8.1%). Laser parameters of 3.54 kW/cm2, 30s obtained the highest energy efficiency of elemental Fe deoxidization, which was 6.33 mg/kJ. The pyrolysis results were consistent with thermodynamic analysis.