BackgroundThe purpose of this study was to investigate the low back pain (LBP) and physical function of young to middle aged farmers of leeks in western Tottori Prefecture. Methods Fifteen farmers (55 years old or younger) cultivating leeks in western Tottori Prefecture were recruited as the subjects, and 14 non-farmers matching the age and sex of the subjects were recruited as the control group. A questionnaire survey was conducted to determine the presence or absence of LBP, smoking, and alcohol consumption. Physical functions were measured by anthropometry (body fat percentage and muscle mass), Finger-Floor distance (FFD), back muscle strength, and upper body bending, and lumbar muscle cross-sectional area (CSA) was evaluated by magnetic resonance imaging (MRI). Results Weight, BMI, body fat percentage, upper body bending, back muscle strength, and L3/4 iliocostalis lumborum CSA, current LBP were significantly higher in the leek farmer group. One-way analysis of variance showed significant differences in upper body bending, and history of LBP. Conclusion LBP was more common among leek farmers. The characteristics of leek farmers with LBP were history of LBP.