Background: There is a need for more research on the health impact of changes in the national unemployment rate. Therefore, the present study was carried out to compare levels of self-rated health during periods of high and low levels of unemployment. Methods: Data included cross-sectional interviews from the Swedish Survey of Living Conditions, which were based on random samples of inhabitants between 16 and 64 years of age living in Sweden. Data were collected for the period 1983–89, when unemployment levels were low (n = 35 562; 2.5%) and for the period 1992–97 when unemployment was high (n = 24 019; 7.1%). Results: After adjusting for sociodemographic variables as well as long-term disease or handicap, the differences in self-rated health between the unemployed and employed were larger when unemployment levels were high in the 1990s, than when they were low in the 1980s. More groups of the unemployed were afflicted with poor health when unemployment was high, compared with when it was low. In 1992–97, being married, living in larger cities, or not having a long-term disease or handicap no longer buffered the negative effects on health among the unemployed. Conclusions: Poorer self-rated health among the unemployed seems to be an increasing public health problem during high levels of unemployment.