OBJECTIVE： To prepare Carbinoxamine maleate sustained-release suspension， and evaluate its quality. METHODS： Using carbinoxamine maleate as raw material， drug-loaded resin was prepared by cation exchange resin； surface coating method was used to finally prepare sustained-release suspension， using Eudragit RS100 as sustained-release coating material to prepare sustained-release microparticles. HPLC was conducted to determine the content of carbinoxamine maleate， release degree of original preparations and self-made suspensions was compared， drug-loading capacity was calculated. RESULTS： The drug amount in preparing drug-loaded resin was 2％， reaction temperature was 25 ℃， and reaction time was 4 h； the drug-loading capacity in surface coating was 35％， amount of coating material was 10％， and reaction temperature was 40 ℃. The drug-loading capacities of sustained particles before and after coating were 35.23％， 32.72％， respectively； the yield was 96.82％. The carbinoxamine maleate in prepared sustained-release suspension accounted for 98.76％ of the labeled amount； release degree in 10 h reached about 80％， f2 was 65.73. CONCLUSIONS： Carbinoxamine maleate sustained-release suspension is prepared successfully， and its release is similar to the original preparation.