Background Overweight and obesity are associated with adverse functional outcomes in people with peripheral artery disease (PAD). The effects of weight loss in people with overweight/obesity and PAD are unknown. Methods The PROVE (Promote Weight Loss in Obese PAD Patients to Prevent Mobility Loss) Trial is a multicentered randomized clinical trial with the primary aim of testing whether a behavioral intervention designed to help participants with PAD lose weight and walk for exercise improves 6‐minute walk distance at 12‐month follow‐up, compared with walking exercise alone. A total of 212 participants with PAD and body mass index ≥25 kg/m ² will be randomized. Interventions are delivered using a Group Mediated Cognitive Behavioral intervention model, a smartphone application, and individual telephone coaching. The primary outcome is 12‐month change in 6‐minute walk distance. Secondary outcomes include total minutes of walking exercise/wk at 12‐month follow‐up and 12‐month change in accelerometer‐measured physical activity, the Walking Impairment Questionnaire distance score, and the Patient‐Reported Outcomes Measurement Information System mobility questionnaire. Tertiary outcomes include 12‐month changes in perceived exertional effort at the end of the 6‐minute walk, diet quality, and the Short Physical Performance Battery. Exploratory outcomes include changes in gastrocnemius muscle biopsy measures of mitochondrial cytochrome C oxidase activity, mitochondrial biogenesis, capillary density, and inflammatory markers. Conclusions The PROVE randomized clinical trial will evaluate the effects of exercise with an intervention of coaching and a smartphone application designed to achieve weight loss, compared with exercise alone, on walking performance in people with PAD and overweight/obesity. Results will inform optimal treatment for the growing number of patients with PAD who have overweight/obesity. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04228978.