Background: The B vitamins can potentially help prevent migraine. This study was designed to examine the effects of supplementation with thiamine (B1), pyridoxine (B6), cobalamin (B12), folic acid (B9), and a combination of these vitamins on women with episodic migraine (EM). Methods: This study was a double-blind, placebo-controlled, randomized, clinical trial conducted on 120 women with EM. The participants were divided into the 6 groups of B1 (n = 20), B6 (n = 20), B12 (n = 20), B9 (n = 20), vitamin B complex (n = 20), and placebo (n = 20). Subjects received 1 capsule daily for 12 weeks. As part of the baseline and post-intervention phases, paper-based headache diaries were used to record the number of abortive drugs consumed and the frequency of headache attacks, and the Migraine Disability Assessment Questionnaire (MIDAS) was used to assess migraine disability. Results: A 16-week study on women with EM revealed that the mean changes in the frequency of headache attacks decreased significantly in all vitamin groups in comparison with the placebo group (P < 0.001). In contrast to the placebo, there was also a significant improvement in the migraine disability score in each vitamin group (P < 0.001). The 12-week supplementation with vitamins B9, B1, B6, B12, and B complex also brought on a significant decrease in the use of abortive drugs compared to the placebo group (P = 0.032). Conclusion: The results of this study showed that B1, B6, B12, and B9, and a combination of these vitamins could be effective as an adjuvant in treatment and prophylaxis of EM. Further large trials with long-term follow-ups will be required to confirm our results.