Objective:To analyze the effectiveness and associated factors of highly active antiretroviral therapy (HAART) on men who have sex with men (MSM) in Jiangsu province,and to establish an evaluation system of HAART for MSM in Jiangsu province for the first time. Methods:MSM who received HAART in two cities in Jiangsu province participated in a cluster random sampling. Questionnaires were used to collect information of life history and drug use. CD4 count was acquired from AIDS therapeutic database of Jiangsu province. Epidata 3.0 and SAS 9.0 were used for data entry and statistical analysis,respectively. Results:According to AIDS therapeutic database,the total CD4 count of 157 MSM was increased,while their drug compliances were quite low. Univariable and multivariable statistical analyses showed that low condom usage,heavy smoking,and long-time interval between definite diagnosis and therapy reduced the effect of HAART,while higher CD4 count at the time of starting therapy and longer drug use were protective factors of HAART. Conclusion:Currently,HAART showed significant effect among MSM in Jiangsu province. We recommended performing early treatment and improving drug compliance of HAART among MSM who meet the therapy conditions.