OBJECTIVES: To assess the comparetive effectiveness and safety of two monophasic oral contraceptives of Marvelon and Minulet METHODS: We searched the electronic databases, MEDLINE, EMBASE, Popline and the Cochrane Library(Issue 4, 2007). Four relevant journals, including Contraception, Internal Journal of Fertility, Chinese Journal of Obstetrics and Gynecology and Chinese Journal of Fertility and Family Planning were hand-searched. Randomized controlled clinical trials(RCTs) on comparetive effectiveness and safety of marvelon and minulet were included. The quality assessment and data extraction were conducted by two authors independently. Revman 4.2 was used to perform meta-analysis. RESULTS: Six trials with 3143 participants were eligible for this review. Results of meta-analyses revealed that during the 6-month follow-up period,no significant difference was found between Marvelon and Minulet in contraceptive effectiveness(p>0.05); participants receiving Marvelon reported more incidences of irregular bleeding[RR=1.50, 95%CI=1.27-1.78; p<0.00001];less incidences of vomitting [RR=0.18, 95%CI=0.04-0.78; p=0.02] , and  more incidences of breast tenderness, nervousness, headache, chloasma, edema, dyspareunia, varicose[RR=1.23-2.69; 95%CI=1.02-6.37 p<0.05]. No significant differences were detected in terms of discontinuation rate between Marvelon and Minulet[RR=0.00-3.28; 95%CI=0.00-79.83; p>0.05] . CONCLUSIONS:While Marvelon and Minulet had comparable effectiveness for contraceptions ,the use of Minulet might render less incidences of irregular bleeding and other common adverse events.  But evidence from more well-designed RCTs recruiting more participants is needed to validate such a conclusion.