Abstract: The present study was carried out to examine contrastive study on learning vocabulary through role-play and memorization among Iranian upper-intermediate EFL female learners. Seventy five Iranian EFL female students learning English in Hegmataneh English institute in Tehran were selected as the sample from the whole upper-intermediate female learners in every English institute in Iran. A pre-test of vocabulary was administered at the beginning of instruction to get convinced that the new words were unfamiliar to participants. Then, the participants were divided into an experimental and control group. There were thirty seven learners in experimental group and thirty eight learners in control group. The students in the experimental group were given the treatment, that is, they learned vocabulary through roleplay during twenty sessions. Whereas the participants in control group were given no treatment, that is, they learned vocabulary through memorization, as a traditional technique. At the end of the treatment, the same pre-test of vocabulary was given as a post-test to both groups, as experimental and a control group, in order to see which technique was more effective in learning vocabulary. By comparison of the mean scores of both groups, the results showed that there was a significant difference between role-play and memorization. Although both groups had promotions in learning vocabulary, experimental group was observed to make much more promotion in learning vocabulary through role-play than the control group.