Dharmakirti was a high ranking scholar-philosopher in Epistemology after Dignaga in Indian Mahayana Buddhism. He inherited Dignaga and made significant Progress. He identifies the objects in cognition to be individuals and concepts in general, which refer to self-aspect (sva-laksana) and common aspects(samanya-laksana) respectively. To go forward, he confirms that there are merely the conrete things which possess effective force of operation. Thereby, strictey speaking, only the self-aspects can truly become objects, and as a result, he focuses his epistemology on the self-aspects. This was affected by the Sautrantika School, and thus has an inclination to empiricism. With regard to the problem of true and false knowledge, he proposes an important condition, namely, the contents of knowledge do not contradict reality, and the foundation of knowledge lies in perception. He also carefully examines the basic essentials of a cognition and finds that they include cognizing subject, cognized object, cognition and cause of cognition. Cognizing subject is the ability of cognition, which is norhing but perception. Perception occurs in embracing the image of the object. Due to the fact that percetion is the source of the image of cognition, and that perception is the cognizing subject, Dharmkirti asserts that the cognition is a sort of self-cognition. As for the cause and result of cognition, they are not different from each other. Rather, they take place simultaneously in the experience of cognition. In a nutshell Dharmakirti’s epistemology is idealistic in nature, carrying slightly a realistic inclination.