Background: Group B Streptococcus (GBS) is an important pathogen in newborns and pregnant women. Objective: The present study was carried out to estimate the prevalence of GBS colonization in pregnant women in Iran. Materials and Methods: This systematic review and meta-analysis was based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis guideline using the national databases including Society for Information Display, Magiran, Irandoc, Iran Medex, and international databases including MEDLINE, Web of Science, Scopus, PubMed, Science-Direct, Cochrane, Embase, Elton Bryson Stephens Company, Centre for Evidence-Based Medicine, Cumulative Index to Nursing and Allied Health Literature, and Google Scholar, published by 01/30/2017. The I2 index was used to measure heterogeneity between the studies. Results: In a total of 667 documents, 30 (4. 49%) were selected. In this study, the prevalence of GBS colonization in 10090 Iranian pregnant women was calculated as 13. 65% [confidence interval (CI): 95%: 10. 56– 17. 45]. Based on geographic region, 24. 63% [CI: 95%: 11. 52– 45. 06] in the West and 8. 75% [CI: 95%: 6. 43– 11. 8] in the East were the highest and lowest areas in Iran, respectively, and were statistically significant (p = 0. 001). Also, with regards to swapping sampling area, Vaginal with 11. 96%, Vaginal and Rectal with 13. 62%, and Anal and Vaginal with 25. 63% were the least to the greatest, respectively, and were statistically significant (p = 0. 001). Conclusion: Therefore, based on the recommendation of Centers for Disease Control and Prevention as reported by the Ministry of Health and Medical education, early diagnosis, and screening of high-risk women should be done at 35– 37 weeks of pregnancy.