Dental plaque has been considered as one of etiology in dental problem. It consists of collection of microorganisms that are formed and firmly attached to the tooth surface and also food deposit. With the mineralization process, dental plaque will transform into dental calculus and lead to periodontal health issues. Dental plaque formation is affected by diet especially food texture. The aim of this study is identifying the correlation between nutrition, microorganisms, and oral health status in dogs and cats. The study was conducted in Prof. Soeparwi Animal Hospital, Faculty of Veterinary medicine, Universitas Gadjah Mada, Yogyakarta, Indonesia within April-September 2020. Six animals (4 cats and 2 dogs) were examined and dental scaling was performed. Dental calculus then was collected and isolated for microbiological purposes. Results showed that all the animals were diagnosed with gingivitis and some of them have been reached into periodontitis. From the anamnesis and clinical examinations, mix diet (dry and wet food) has been given for daily routine by the owners. Another finding, Streptococcus alpha hemolytic has been found in all the dental calculus samples. The conclusion of this study was nutrition affect the oral health status of the animals