Introduction: The Fallopian tube plays an essential role in tubal transport of both gametes and embryos. Methotrexate is used as an alternative to surgical management of ectopic pregnancy. Methotrexate is considered a folic acid antagonist. Aim of the work: The aim of this study was to study the potential protective effect of folic acid on uterine tube mucosal damage caused by methotrexate in adult female rats. Materials and methods: 18 adult female albino rats were used .The animals were divided into three groups each of them consists of 6 rats: Group I: (control group): were injected with intra-peritoneal saline. Group II: were intra-peritoneal injected with Methotrexate in a dose of 5mg/kg /day for 10 days. Group III: were intra-peritoneal injected with methotrexate at a dose of (5mg/kg/day) plus folic acid at the dose of (0.1 mg/kg) 24hrs after methotrexate injection for 10 days. At the end of the experiment, the rats were sacrificed by decapitation then the ampulla of fallopian tube was obtained and subjected to light and transmission electron microscopic studies. Results: Methotrexate markedly affected both epithelial and smooth muscles of fallopian tube at light and electron microscopic examination and morphmetric studies. Administration of folic acid could attenuate these changes. Conclusion: Methotrexate caused disturbance of tubal epithelium and destruction of its cells. Folic acid can decrease Methotrexate-induced destruction of tubal epithelium.