The relationship between fire ants (Solenopsis spp.) and muskrats (Ondatra zibethicus) was investigated in Louisiana coastal marshes because of persistent reports of ant depredation on young muskrats. Two different marsh types in southwestern and southcentral Louisiana were selected for study. During May-June of 1974 and 1975, 50 muskrat houses were opened on each study area; 50 additional houses were examined during January 1976 on the western study area. There were no significant year or area differences in the proportion of houses which were active or which contained ants. A significantly higher (P<0.10J proportion of houses contained young in May-June than in January. Ofthe houses examined in May-June, there was no significant overall relationship between the absence and presence of ants and whether or not a house was either active or contained young. No antogonistic behavior between fire ants and muskrats was observed.