Objective: To assess the effectiveness of customized insole in patients with Morton’s neuroma. Design: Double-blind randomized controlled trial with intent-to-treat analysis. Setting: Outpatients, University Hospital. Subjects: A total of 72 patients with Morton’s neuroma met the inclusion criteria and were randomly allocated to either the study group ( n = 36) or the control group ( n = 36). Interventions: The study group was assigned to use a customized insole with metatarsal and arch support made of ethyl vinyl acetate and the control group received a flat insole of the same material, color, and density. Main measures: The primary outcome measure was walking pain intensity measured by the visual analogue scale. The secondary outcomes were as follows: pain at rest, palpation, and paresthesia (visual analogue scale); functional disability (6-minute walk test, Foot Function Index, and Foot Health Status Questionnaire); quality of life (Health Survey Short Form-36 (SF-36)); and foot pressure (AM Cube FootWalk Pro program). Results: In the comparison between the groups over time, a statistically significant difference, with improvement in favor of the experimental group, was found for pain during walking ( P = 0.048); in the general health domains ( P < 0.001) and physical activity ( P = 0.025) of the Foot Health Status Questionnaire; in the general Foot Function Index score ( P = 0.012); and in the functional capacity domain of the SF-36 questionnaire ( P = 0.046). For the other parameters, no difference was found between groups. Conclusion: The study demonstrated that customized insole with metatarsal and arch support relieved walking pain and improved patient-reported measures of function in patients with Morton’s neuroma.