The present quantitative study aimed to investigate the effect of contrastive phonics instruction on Armenian-Persian bilingual and Persian monolingual female EFL learners' pronunciation. To this end, 30 homogenous learners, ranging between 8 and 13 years old, in pre-intermediate level were selected from Iran. The paired samples t-test conducted revealed that there has been a significant change between the means of both groups from pretest and posttest which ensure the fact that phonics instruction is an useful method for teaching sounds and it has a positive effect on EFL learners pronunciation. Also the Independent samples t-test administered indicated that there has been a difference between pretest and posttest scores of bilinguals and monolinguals and it was obvious that the Armenian-Persian bilinguals outperformed the Persian monolinguals.