Outcome data comparing patients with multiple primary invasive cutaneous malignant melanomas (MPMs) to single primary invasive cutaneous malignant melanomas (SPMs) show conflicting results. We have analyzed differences in disease-specific survival between these patients in a nationwide population-based setting. From the Swedish Melanoma Register, 27,235 patients were identified with a first invasive cutaneous malignant melanoma (CMM) between 1990 and 2007, followed-up through 2013. Of these, 700 patients developed MPMs. Cox proportional hazard regression was used for adjusted cause-specific hazard ratios (HRs). An interval of =5 years between CMM diagnoses was significantly correlated to a decreased CMM-specific survival in Stage I-II MPM- vs. SPM-patients (HR 1.32; 95% CI 1.04-1.67; p?=?0.02). MPM-patients with longer time interval between diagnoses experienced similar risk of CMM-death as SPM-patients. The risk of CMM-death increased by almost 50% above the expected outcome according to stage of the index CMM by the diagnosis of a second CMM (HR 1.48; 95% CI 1.19-1.85; p?