Q fever is a zoonotic disease caused by the bacterium Coxiella burnetii. Its prevalence among farm animals is important to both public and animal health. The aim was to investigate the presence of C. burnetii in cattle, sheep and goats. Three hundred samples consisted of pooled milk and serum 180 of each from dairy cattle (n=180) dairy goats (n=60) and dairy sheep (n=120) from Qaliubia, Monofia, Gharbia and Kafr ElSheikh Governorates. All samples were examined by indirect immunofluorescent antibody technique (IFAT) for IgG antibodies against C. burnetii phase II antigen. The prevalence of antibodies in dairy herds was 22.5 % with large regional differences. The study revealed that antibodies against C. burnetii in cattle raw milk and sera were 14.44% and 31.11%, respectively, in goat raw milk and sera were 26.67% and 46.67%, respectively and in sheep raw milk and sera were 21.67% and 33.33%, respectively. These results denoted that, the apparently healthy cattle, sheep and goats are an important reservoir of C.burnetii infection. Coxiella burnetii is shed in milk of the infected animals; therefore, their milk should not be consumed raw or sold unpasteurized directly to the consumers. Pasteurization of milk is carried out at 145° F (63° C) for at least 30 minutes or at 161° F (72° C) for 15 seconds is sufficient to destroy C. burnetii, as well as other pathogens that can be present in raw milk. Finally, we conclude that it is of utmost importance to avoid contact with the placenta, birth products, fetal membranes, and aborted fetuses of sheep, cattle, and goats. On the other hand eating and drinking unpasteurized milk and milk products pose a great risk of infection to man and should be avoided.Further investigation is recommended concerning C. burnetii prevalence in the aborted cases of farm animals.