Saccharin and ethanol intakes were measured in seven strains of rats known to differ in their preferences for ethanol: The Fawn-Hooded (FH), alcohol-preferring (P) and Maudsley Reactive rats have been reported to drink ethanol voluntarily, whereas the alcohol-nonpreferring, Maudsley Nonreactive and Flinders Line (FSL and FRL) rats do not. Saccharin and ethanol intakes were highly correlated (r = +0.61) over all strains, with the FH rats drinking the most of both solutions. Correlation coefficients between pairs of drinking versus nondrinking rat strains were even higher. In a second experiment, genetically heterogeneous F2 progeny from cross-breeding the ethanol-preferring FH rats with the ethanol-nonpreferring Flinders Resistant Line (FRL) rats were studied. The results indicated a high positive correlation between saccharin and ethanol intakes (+0.65). These findings suggest that the association between saccharin and ethanol intakes previously reported in rat strains with different preferences for ethanol may have a similar genetic basis.