CONTEXT Insertion pain or fear of it may make women hesitate to use the intrauterine device (IUD); a long-term, reversible, highly-effective contraception method. Further study has been recommended on the effects of lidocaine (xylocaine) gel on IUD insertion pain in the recent Cochran review. AIMS To determine the effect of lidocaine gel on pain from TCu-380AIUD insertion. MATERIALS AND METHODS At a health center in Tabriz, Iran, 96 women were allocated into 3 groups using block randomization with 6 and 9 block sizes considering allocation concealment. In 1 st group, lidocaine 2% gel and in the 2 nd , lubricant gel was placed in the cervical canal 1 minute before an IUD insertion, and the 3 rd group got no intervention. Immediately after IUD insertion, pain during the insertion was measured using 0-10 cm visual analogue scale. STATISTICAL ANALYSIS USED Kruskal-Wallis and linear regression in SPSS-13 were used to identify effect of lidocaine gel on the pain. RESULTS Overall, the mean pain score was 3.5 ± 1.8. In univariate analysis, there was no significant difference in pain scores between the 3 groups. Also, results of linear regression model by controlling effect of the possible confounding showed no significant effect of lidocaine gel on the insertion pain. The mean pain score in the lidocaine group was 0.39 less than the no intervention group, but it was not significant (CI 95% of the difference: -1.3, 0.57). CONCLUSIONS Use of 2% lidocaine gel into the cervical canal has no effect on reducing overall pain during IUD insertion.