Abstract: The leaching performance of a marlite-dolomite Uranium Ore has been studied.Although the uranium extraction rate can get above 90% with 816kg/t sulphuric acid consumpton,but, there are some difficulties on technique and economy,so acid lixiviant can not be used to leach uranium with tish roe.Experiment results indicated that 45g/L Na₂CO₃+15g/L NaHCO₃ is the best lixiviant.The uranium extraction rate is about only 60% and and only a little increasing added oxidant with alkaline leaching under ambinet temperature.It can get to above 70% with 10% increasing with heating compared with alkaline leaching under ambient temperature.More technical studied should be done to get higher leaching rate.