introduction: Folic acid is an important nutrient for maintaining and improving health and its deficiency during pregnancy increase the risk of spontaneous abortion, neural tube defects, preeclampsia, placental abruption, preterm labor, low birth weight and anemia. These risks can be prevented by increasing folic acid intake during pregnancy and pre-conception. Therefore, this study was performed with aim to determine the level of knowledge and consumption of Folic acid in pregnancy and pre-conception through meta-analysis. Methods: In this systematic review and meta-analysis study, for finding the related articles, the Persian and English journals which were indexed in databases of SID, Iranmedx, Irandoc, Magiran, Scopus, and PubMed were searched with Mesh keywords up to August, 2018. I2 index was used to assess the heterogeneity in the studies. Data were analyzed by meta-analysis method using random effects model. Results: Of the 2366 articles found in the primary search, 16 articles were selected for systematic review and meta-analysis. In the meta-analysis, according to the random effects model due to heterogeneity 97%, these results were estimated: hearing the name of folic acid by women in 84. 8% (77. 5-90. 1), knowledge of women from the role of folic acid in 37. 2% (27. 5-48. 1), knowledge of the time of taking folic acid in 27. 3% (17. 9-39. 3), knowledge of the correct dose of folic acid in 75. 2% (63. 3-84. 2), use of Folic acid during pregnancy in 74% (65. 2-81. 6), use of folic acid in pre-pregnancy in 18. 3 % (12. 6-25. 9), regular consumption in 47% (7. 8-90. 3), and irregular consumption of folic acid in 40. 9% (9. 1-82. 7). Conclusion: The level of knowledge of women at reproductive age about folic acid complementary and its valuable role in pregnancy is not desirable. Since health personnel are the most important source of information on the use of folic acid, so they have to work more efforts in this regard to increase the level of women's knowledge.