Evaluate changes from baseline in health-related quality of life (QoL) in Japanese patients with episodic migraine receiving preventive treatment with galcanezumab (GMB). Preventive treatments for migraine have been shown to improve QoL, but few clinical trials have examined QoL outcomes in Japanese patients. This phase 2, randomized, double-blind, placebo-controlled study was conducted at 40 centers in Japan. Patients aged 18-65 years with episodic migraine (4-14 monthly migraine headache days) received GMB 120 mg (n=115), 240 mg (n=114), or placebo (PBO, n=230) as monthly subcutaneous injections for 6 months. QoL was measured monthly using the Migraine-Specific Quality-of-Life Questionnaire (MSQ) version 2.1. Prespecified analyses were differences between GMB and PBO for change from baseline in all 3 domains of the MSQ and MSQ-Total, for each month and the average over Months 4-6. Treatment with GMB significantly increased MSQ scores from baseline vs PBO. Average change ± SE from baseline across Months 4-6 was 10.12±0.72 (PBO), 17.13±1.03 (GMB 120 mg; <0.001), and 15.91±1.03 (GMB 240 mg; <0.001) for MSQ Role Function-Restrictive; 4.80±0.65 (PBO), 9.64±0.93 (GMB 120 mg; <0.001), and 8.35±0.93 (GMB 240 mg; <0.05) for MSQ Role Function-Preventive (MSQ-RFP); 3.46±0.77 (PBO), 10.04±1.10 (GMB 120 mg; <0.001), and 7.73±1.10 (GMB 240 mg; <0.05) for MSQ Emotional Function, and 7.14±0.67 (PBO), 13.46±0.95 (GMB 120 mg; <0.001), and 11.98±0.95 (GMB 240 mg; <0.001) for MSQ-Total. Significantly greater improvement in scores in all MSQ domains and MSQ-Total was observed for both GMB doses vs PBO at Month 1 and was maintained for Months 1-6 (excluding Month 5 for MSQ-RFP). Preventive treatment with GMB 120 mg/240 mg improves MSQ scores in Japanese patients with episodic migraine. Improvements were seen within the first month and maintained for 6 months and are similar to those seen in global studies enrolling primarily Caucasian patients. ClinicalTrials.gov, NCT02959177 (registered November 7, 2016).