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PURPOSE: To assess the severity of peripheral neuropathy (PN) on lateral gastrocnemius Hoffman reflex (H-reflex, both H/M ratio and H-index) modulation during walking stance phases (heel-contact, mid-stance, and toe-off). METHODS: Thirty-two participants were recruited in this study. Nine of them were in the Control group (healthy population) with intact plantar sensitivity. Twenty-three of them with doctordiagnosed PN. The participants with PN were further divided into two groups based on their plantar pressure sensitivity: the less affected group (scored 6-9 points), more affected groups (scored 0-5 points). Plantar pressure sensitivity was assessed with 5.07-gauge monofilaments at the hallux, bases of first/fifth metatarsals, mid arch, and heel. H-reflex of lateral gastrocnemius was collected during three stance phases (Heel-contact, Midstance, Toe-off). RESULTS: No group by stance phases interaction detected in H/M ratio (p=0.245). The mean H/M ratio of the three phases was significantly different across all three groups (p=0.049, partial η2=0.200) with no group main effect detected (p=0.407). The H/M ratio of Midstance (11.1±1.8%) was greater than that of Toe-off (9.4±1.7%, p=0.024, d=0.537). No significant difference was observed between H/M of Heel-contact (10.3±1.7%) and Midstance or Toe-off. No significant interaction was detected in H-index either. No phase nor group main effects were detected for H-index. CONCLUSIONS: The deficiency in plantar sensitivity did not affect the gastrocnemius H-reflex, both H/M ratio and H-index, during the walking stance phase. [ABSTRACT FROM AUTHOR]