Objective To evaluate the effectiveness of Medicated γ-IUD compared with other IUDs for contraception. Methods CBMdisc (1986 -2005), VIP (1989 -2005) , CNKI (1994-2005) , The Cochrane Library (Issue 4, 2005 ) and 10 related journals were searched for randomized controlled trials (R.CTs) and quasi-randomized controlled trials (quasi-RCTs) on the comparison between γ-IUD and other IUDs. The quality of included trials was critically appraised. RevMan 4.2.8 software was used for statistical analysis. Results Ten published studies with 8 381 participants were included. The results of meta-analysis were expressed with Peto OR ( cumulative pregnancy rate, cumulative expulsion rate, cumulative rate of removing for medical reasons) or OIL ( cumulative continuation rate ) and 95% CI. Compared with MSSR-165, Medicated γ-25,200 resulted in lower pregnancy rate at 1, 2, 3 years of follow-up [ with the OR (95% CI) 0. 31 (0.15,0.64) , 0. 31 (0. 17,0.54) , 0. 31 (0.19,0. 51) , respectively], lower cumulative expulsion rate in5 year follow-up [0.26 (0.17,0.40), 0.28 (0.20,0.41), 0.30 (0.21,0.42), 0.29 (0.19,0.44), 0.32 (0.21, 0. 48 ), respectively], lower cumulative rate of removing for medical reasons.after 4 year follow-up [0.57 (0.36,0. 92 ) ], and higher rate of cunmlative continuation in 5 years of follow-up 13.35 ( 2.29,4.89 ) , 2.76 ( 2.06,3, 69 ) , 2.41 (1.89,3.08), 2.22 (1.69,2.91), 1.99 (1.55,2.55), respectively]. Compared with TCu220, Medicated γ-25,200 resulted in lower cumulative pregnancy rate after follow-up 2, 3 years [ 0.46 (0.25 ,0.87 ) ; 0.48 (0.27,0. 85 ) ], lower cumulative expulsion rate after 1 year follow-up [ 0. 58 (0.35,0.97) ] , lower cumulative rate of being removed for medical reasons in5 year follow-up [0.37 (0.23,0.59), 0.38 (0.26,0.56), 0.45 (0.32,0.64), 0.47 (0.30,0.73), 0.58 (0.39,0.87), respectively ] and higher rate of cumulative continuation in 5 years of follow-up [ 2. 15 ( 1.61,2.87 ), 2.02 ( 1.56,2.63), 1.72 ( 1.34,2.20), 1.44 ( 1.08,1.91 ), 1, 39 ( 1.07,1.80), respectively]. Compared with Uterus-Cu, Medicated γ-25,200 resulted in higher rate of cumulative continuation after follow-up 1 year [ 0.51 (0.34, 0.77) ]. Compared with MLCu375, Medicated γ-25,200 resulted in lower cumulative rate of being removed for medical reasons and higher rate of cumulative continuation after follow-up for 3 years [ 0. 22 (0.09,0.52) , 2.84 ( 1.64,4. 94 )]. Compared with TCu380A, Medicated γ-25, 200 resulted in lower cumulative rate of being removed for medical reasons and higher rate of cumulative continuation in follow-up for 2 years [ 0.36 ( 0.18,0.73 ), 0.29 ( 0. 12,0.70 ) ; 3.06 ( 1.72,5.44), 3.61 (1.75,7.47) ]. Conclusions Available evidence shows that Medicated γ-IUD has better or equal effectiveness when compared with other IUDs. However, more RCTs with high quality and longer follow up period are needed to confirm the conclusion.