The moderating effect of level of education (as an indicator of socioeconomic status) on the associations between chronic medical morbidity and six domains of health-related quality of life (physical function, role function, social function, health perceptions, bodily pain and mental health) is studied in a large community-dwelling elderly sample (N = 5279). The results showed that health-related quality of life is substantially affected by chronic medical morbidity, and that level of education has weak, but significant unique contributions to physical function, social function, health perceptions, and mental health. We did not find substantial evidence for the differential vulnerability hypothesis. At best, low education might amplify the negative effects of the number of chronic medical conditions on mental health only, but this result was not confirmed in four specific disease groups.