Objective：We identified the factors that influenced the effect of the Wearable Cyborg Hybrid Assistive Limb (HAL) in patients with amyotrophic lateral sclerosis (ALS).Methods：The subjects were patients with ALS who were admitted to our hospital, and all of them underwent HAL intervention. The changes in 2-minute walking distance (2 MD) before and after 1 course of HAL intervention were investigated. Next, we examined the factors that influence the degree of 2 MD improvement using patient attributes and indices of body composition, nutritional status, respiratory function, and ADL (Activities of Daily Living) before HAL intervention.Results：Thirteen subjects showed significant improvement in 2 MD measured before and after the HAL intervention (median 2 MD [quartile] before intervention－median 2 MD [quartile] after intervention：36.0 [32-94.49] m－74.1 [32.75-117.8] m, p＝0.001). The Barthel Index (BI) and phase angle were identified as the factors that influenced the degree of 2 MD improvement (ANOVA：p＝0.004).Conclusion：The results suggest that the degree of improvement in 2 MD by HAL intervention in patients with ALS was the most affected by their BI and phase angle before the intervention. Thus, BI and phase angle may be useful as predictors in the degree of 2 MD improvement by HAL intervention in patients with ALS.