The contemporary Australian Doctoral Education is marked with a new feature: diversified doctoral programs. Apart from the traditional way of attaining a doctoral degree through a dissertation, several rising doctoral programs such as External Phi), Professional Doctorate, Doctoral program cooperated with the enterprise or with foreign universities also develop rapidly. This paper carefully studies the manifestation of the diversified doctoral programs, induces and analyzes the causes of diversity. It also points out the main barriers of the development of the diversified doctoral programs and discusses its diversity under the knowledge economy background.