We investigated the role of the western grey kangaroo (Macropus fuliginosus) in the maintenance and transmission of Coxiella burnetii in Western Australia. Sera from 1,017 kangaroos were tested using an indirect enzyme-linked immunosorbent assay (ELISA) for the presence of C. burnetii antibodies. The overall antibody prevalence across 12 locations throughout mid- to southwestern Western Australia was 24.1% (95% CI: 21.6–26.8). Feces from 990 of the same animals were tested using PCR to identify active shedding of C. burnetii in excreta. Coxiella burnetii DNA was detected in 4.1% (95% CI: 3.1–5.6) of samples. Our results suggest that kangaroos are reservoirs for C. burnetii in Western Australia and may contribute to transmission of the organism to domestic livestock and humans.