BACKGROUND: The bacterium Capnocytophaga canimorsus is a relatively newly recognized gram-negative, facultative, slow-growing bacillus that forms part of the normal oral flora of dogs and cats. Considering the pathogenicity of this bacterium in humans, determining its prevalence is very important for public health as well as the health of dog owners.OBJECTIVES: This study aims to investigate the prevalence of Capnocytophaga canimorsus in the normal oral flora of healthy dogs.METHODS: After taking samples from the saliva of 32 healthy dogs without oral, dental or digestive diseases at different ages, breeds, and sexes, they were placed in a test tube containing 10 mL of sterile peptone water with sterile plastic brushes, and immediately sent to the bacteriology laboratory under sterile conditions. The samples were cultured on a chocolate agar medium containing 5 % defibrinated sheep blood. Then, all the samples were kept in a greenhouse for 48 hours at a temperature of 37 °C and under anaerobic conditions. Using a loop, the grown pink colonies were isolated and to confirm the identification of the isolates, polymerase chain reaction (PCR) test was used in three main steps: Gene extraction, PCR reaction, and electrophoresis.RESULTS: Out of 32 saliva samples, four positive cases of Capnocytophaga canimorsus bacteria were identified by PCR diagnostic method.CONCLUSIONS: Given that Capnocytophaga canimorsus bacterium is present in the oral flora of healthy ​​dogs, dog owners should have sufficient and favorable knowledge about this bacterium and related diseases. The PCR method can be used to detect this bacterium.