Effects of solvents such as ethanol, isopropanol and acetone on the qualities of chloroquinoline sulfate such as color, clarity, melting point and crystalline form are studied in detail. The results indicat that a single solvent of ethanol or isopropanol makes end_product greenish with an indefinite melting point but an excellent clarity and a relatively high yield; a single solvent of acetone, however, greatly improved the color and the stability of melting point, but decreased the yield and the clarity. Based on the results above, the mixture of these solvents are required to get the optimum of this product. An optimum solvent composed of V (ethanol(95%)): V (acetone)=1:4 are determined and used to prepare chloroquinoline sulfate, whose qualities are up to BP93.