This study was aimed to evaluate and compare the nutrient digestibility of grain-inclusive and grain-free commercial dry dog foods using the method of total fecal collection and also explore their effects on fecal consistency. 21 different foods, including 14 grain-inclusive (7 grain-chicken meat, 7 grain-lamb meat) and 7 grain-free were investigated. 12 adult Golden retriever dogs (age 3–4 years, body weight=22.5±1.7kg) were divided into 3 groups. The results of digestibility trials indicated that the grain-lamb meat foods showed the highest digestibility of dry matter, organic matter, and crude fiber. Overall, in the grain-inclusive and grain-free group evaluation, grain-inclusive foods showed higher digestibility of crude fibers while grain-free foods had higher ether extract digestibility whereas the differences in the scores of fecal consistencies between the groups were insignificant. Contrary to popular belief, grain-inclusive foods were more digestive than grain-free foods in terms of dry matter and organic matter. There are studies involving starch sources in the dog food formulations, but there is a need to study the digestibility of complete dog food to supply them with adequate nutrients. Also, each diet should be assessed based on its overall nutrient profile and digestibility rather than individual ingredients.