Objective:To prepare cyclosporine A ( Cs A) microemulsion gels and investigate the quality. Methods:Cs A microe-mulsion gels were prepared, then the quality was evaluated using the physicochemical properties, particle size and distribution, content of Cs A in the microemulsion gels and rheological properties as the indices, and the stress testing and stability experiment were used to evaluate the quality as well. Results:The results showed that the physicochemical parameters were within the required ranges, the par-ticle size was uniform below 50nm, the method of determination was easy and accurate, and the rheological study revealed the gels were pseudoplastic fluid. The stress testing and stability experiment showed that the preparation could not be influenced by high temperature and highlight for 6 months at 60℃. Conclusion:The preparation is suitable for the ophthalmic use.