Abstract: The problem of difficult separation of low concentration calcium ions in manganese sulfate ore solution is not conducive to its further utilization. This study compared the effects of fluorination and ammonification methods on the separation of calcium from sulfuric acid manganese ore solution, and investigated in detail the effects of ammonium fluoride dosage, pH value regulator, ammonium carbonate precipitant dosage, reaction temperature, and pH value value on calcium separation efficiency and manganese ion loss. Experiments have shown that the optimal conditions for separating calcium by fluorination are: adjusting the pH value to 4.5 using ammonia water, a ratio of 3:1 between ammonium fluoride and manganese, a ratio of 3:4 between ammonium carbonate and manganese, and a reaction temperature of 90 ℃. The optimal pH value for separating calcium by ammonification method is 9.5. It is worth noting that both methods can not only separate low concentrations of calcium, but also achieve a separation rate of over 90% for magnesium. Compared to the fluorination method, the ammonification method can achieve a calcium separation rate of 83.3% and minimize the loss of manganese ions. In addition, high-purity manganese carbonate was successfully prepared by further utilizing the manganese ions in the manganese sulfate solution obtained by the ammonification method for separating calcium and magnesium.