Current understanding of the epidemiology and outcomes for patients with multiple myeloma in Finland is scarce due to lack of comprehensive real-world evidence in clinical practice. The aim of this study was to gain understanding of epidemiological characteristics and treatment and survival outcomes by utilizing multiple real-world data sources with information of adults treated for active multiple myeloma (MM) during years 2005-2016 in Finland. A total of 3851 adult MM patients with C90.0 diagnosis fulfilling all inclusion criteria were included in the analysis. The average myeloma incidence was six cases per 100,000, which slightly increased (p = 0.011) during the follow-up. The age-standardized incidence was three cases per 100,000 in the years 2005-2016. On average, 25% of patients received autologous stem cell transplantation (ASCT), and this proportion increased during the years 2005-2015 from 17 to 30%. The majority of patients under 65 years of age received ASCT treatment (60.5%), whereas only 8.7% of patients 65 years of age or older were treated with ASCT. The net median overall survival improved by approximately 5 months from 2005-2010 (3.44 years) to 2011-2016 (3.89 years); after adjusting for covariates, this presented an annual 4% reduction in the risk of death. Longer median survival and decreased risk of death indicate improved treatment outcomes from 2005 to 2016 among adult MM patients in Finland.