Malignant melanoma, a neoplastic disorder produced by malignant transformation of the melanocyte, is considered to be resistant to chemotherapy. Dacarbazine is one of the standard chemotherapeutic agents in Korea. This study is designed to analyze treatment outcome and delineate prognostic factors based on clinical parameters for patients with advanced malignant melanoma who had received dacarbazine-based chemotherapy. This is a multicenter, retrospective analysis of 95 patients with metastatic malignant melanoma who had received dacarbazine-based chemotherapy, from January 1997 to June 2010. After a median follow-up duration of 41 months (range, 2-191 months), median survival time from the start of treatment was 12.1 months [95% confidence interval (CI): 10.9-13.5]. The overall response rate was 26.3% (95% CI: 17.8-36.4). On univariate analysis, primary site [mucosa of head and neck, gastrointestinal (GI)/genitourinary tract > cutaneous+acral melanoma], metastases to liver, GI tract, and elevated lactate dehydrogenase adversely influenced on survival. At a multivariate level, independent poor prognostic factors were mucosal melanoma [P=0.001; hazard ratio (HR): 2.988; 95% CI: 1.534-5.821], metastasis to GI tract [P=0.040; HR: 2.108; 95% CI: 1.036-4.288], and elevated lactate dehydrogenase (P=0.047; HR: 1.695; 95% CI: 1.007-2.854). Dacarbazine-based chemotherapy seems to be a reasonable option in Asia where mucosal melanoma is more prevalent than in the West. The dacarbazine-based chemotherapy showed an overall response rate of 26.3% and an overall survival of 12.1 months without a significant difference in response rates between noncutaneous or cutnaeous melanoma.