In order to understanding the competitive relationship among predators and planning a conservation program for the wildlife around Beijing, 85 feces samples of carnivores were collected by a strip-sampling method at two scenic spots (Songshan, and Yunmengshan) and one nature reserve (Wulingshan) in 2002, which mainly belonged to Vulpes vulpes and Nyctereutes procyonoides of Canidae, Mustela sibirica and Arctomyx collaris of Mustelidae, and leopard cat (Felis bengalensis) of Felidae. And then the food habits of animals were studied by feces content analysis. The results revealed that the small mammals were the main food and the percentage of occurrence of rodents in the total samples was 82.4%. The second and third orders of foods were plants (54.1%) and birds (31.8%) respectively. But the occurrence rates of big preys of roe deer (Capreolus capreolus) and hare (Lepus capensis) were only 8.2%. The main foods of canids were the voles, plants and murid species. Whereas the plants took the first place (72.4%) in the analyzed samples of leopard cat, and birds (62.1%) and murid species (48.3%) took the following order places. The remains of plastic products had a higher occurrence rate at the areas with intensive tourism. The relationship of co-existence and competition among the predators was discussed through the comparison of food niche overlap. It suggested that the leopard cats took more birds and murid species as a food divergence to co-exist with other predators.