OBJECTIVES: To examine the quality of life (QoL) of the Alzheimer’s Disease (AD) patients in relation to disease progression during the five-year ALSOVA follow-up study. METHODS: The baseline sample consisted of 240 subjects with very mild or mild AD, 65 years or older, from three Finnish hospital districts. The subjects were recruited between 2002 and 2006, and were followed-up for five years. Three separate patient-reported wellbeing and life satisfaction instruments were used as proxy variables for QoL: a generic, preference-based health-related quality-of-life instrument, 15D; an AD -specific wellbeing measure, AD-QOL; and a VAS-based life satisfaction scale. AD progression was evaluated with the Clinical Dementia Rating (CDR). Both CDR Sum-of-Boxes (CDR-SOB) and global rating were used in the analysis. Generalized linear mixed models with hierarchical structure were applied to account for repeated measures and possible clustering by the hospital district. Data were adjusted for age, sex and years of education. RESULTS: On average, none of the three outcome measures demonstrated statistically significant changes over time during the five year follow-up. However, when the outcomes were examined in relation to AD progression, both CDR-SOB and CDR global rating demonstrated statistically significant association between the severity of AD and lower QoL on all three outcome measures.  However, when using CDR global rating to define disease progression, we observed meaningful impairments in QoL variables only in the patients with severe AD (CDR 3). CONCLUSIONS: Severe AD has a considerable impact on patients’ QOL through substantial impairments in wellbeing and life satisfaction. Evidence suggest that CDR-SOB is a potential continuous measure of AD severity. While CDR-SOB is strongly associated with decrease QoL measures, our observations indicate that it is unlikely to be linearly correlated with QoL. Thus, the use of CDR-SOB as a determinant of QoL needs to be examined further.