Abstract:High content of carbonates is prone to cause chemical blockage during acid or alkaline in situ leaching for uranium mine at a sandstone-type deposit. The field pilot experiment of low acid neutral in situ leaching was conducted with 0.3 g/L of sulfuric acid solution as leaching agent, and hydrogen peroxide and oxygen as oxidants. PH value of leaching system is controlled at level of 6.1~6.7 to avoid calcium carbonate precipitation. Content of Ca2 and SO42- does not exceed 900 mg/L and 2100 mg/L respectively to control calcium sulfate precipitation. Reaction between acid and carbonates produces 400~450 mg/L of HCO3-, which can be used as complexant of uranyl. Recovery uranium concentration is 24~31 mg/L with oxidation of hydrogen peroxide, and it rises to 48~62 mg/L by 300~350 mg/L of oxygen. Compared with conventional acid or alkaline leaching process, low acid neutral leaching technology facilitates uranium leaching and avoids precipitation of both calcium sulfate and calcium carbonate.