We first report a case of patient with refractory dermatomyositis (DM) who successfully treated with tumor necrosis factor-alpha blocker, etanercept and developed necrotizing fasciitis (NF) after the use of it. NF was diagnosed early by MRI and managed with antimicrobial therapy and timely debridement of necrotic tissue with favorable outcome. We suggest that etanercept can be a useful therapeutic agent in patients with DM refractory to steroid and immunosuppressive agents and NF may occur in DM in association with etanercept therapy. We also suggest that management strategies for early diagnosis and treatment are needed for this complication.