This study was performed for isolation and identification of the aerobic bacteria from materials which collected from the 66 healthy breeding bitches' vagina in different race, age and estrous cycle at the Military Veterinary School and Training Center Commandership Gemlik/ Turkey. After the samples taken, vaginal cytology is applied to each dog to determine dog's estrous cycle period. Seventy five microorganisms isolated from 62 (%93.94) of 66 bitches in different races. Twenty E.coli (26.67%). 20 Staphylococcus spp. (26,67%), 12 Salmonella spp. (16,0%), 5 Candida spp, (6,67%), 5 Micrococcus spp. (6,67%), 4 Streptococcus spp. (5,33%), 4 Acinetobacter spp. (5.33%), 3 Neisseria spp. (4.0%), 1 Bacillus spp. (1,33%). 1 S.aureus (1,33%) were identified. This study confirms that aerobic bacteria Isolated from genital tract of healthy bitches at different estrous cycle period do not cause infertility Therefore microbiological examination of vaginal swaps may be necessary in infertil dogs.