The purpose of the study was to investigate the factor structure of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) among Finnish nursing staff. Although the factorial validity of the MBI-HSS has been studied across different countries, the factor structure has never been investigated among Finnish nursing staff. The data were gathered by postal questionnaires from nursing staff working in health-care organizations around Finland. The sample consisted of 627 nurses and nurse managers. The factor structure was studied by using exploratory and confirmatory factor analysis. The fit of the hypothesized three-factor model to the data was superior to the alternative one-factor and two-factor models. The three-factor structure (emotional exhaustion, depersonalization, reduced personal accomplishment) showed the best fit, while the internal consistencies of the subscales were satisfactory. The MBI-HSS is a highly suitable instrument for measuring burnout among nursing staff and it is very applicable to Finnish health-care research.