Objective: To evaluate the feasibility and psychosocial outcomes of an Acceptance and Commitment Therapy (ACT)–based group resilience training program for people with multiple sclerosis (PwMS). Research Method/Design: The study used a pre–post group intervention design with 3-month follow-up. The intervention consisted of 8 group sessions of 2.5 hours each with 7 weekly sessions plus a booster Session 5 weeks later. Thirty-seven PwMS completed questionnaires. Primary psychosocial outcomes were resilience, quality of life (QoL), and distress. Secondary outcomes were the ACT processes: mindfulness, defusion, values and acceptance. Results: Significant improvements were observed for resilience (p = .005; Hedge’s g = .47), physical health QoL (p < .001; g = −.76), mental health QoL (p = .006; g = −.46), depression (p = .009; g = .38), stress (p = .025; g = .33), and 3 ACT processes: defusion (p = .013; g = −.54), values (p = .010; g = −.38), and acceptance (p = .006; g = −.39). Values and defusion emerged as mediators of physical health QoL and stress (90% CI), respectively. Program feasibility was supported by positive participant feedback; high rates of recruitment, attendance, retention, and homework engagement; and good intervention fidelity. Conclusions: Findings provide preliminary support for the utility and feasibility of a community organization delivered ACT-based group resilience training program for improving resilience, QoL, depression, stress, and protective factors (defusion, values, acceptance) in PwMS.