Since the founding of the People's Republic of China, space science has lived within the cracks of the nation's space program, clearly secondary to technological and national security goals. Today, although China has a large and growing aerospace sector, space science remains underdeveloped. This article reviews the emergence and development of space science in China through four periods by examining five primary factors: the policy priority attached to space science, the organization of space science, planning activities and budgetary commitments, international exchanges, and the technical capabilities that underlie the program. Several science projects, which include astronomical satellites, space solar telescopes, a Hard X-Ray Modulation Telescope, the "Double Star programme" and pilot projects in space science of the Chinese Academy of Sciences, will be considered. The article demonstrates that China not only possesses a rapidly developing and increasingly complex space program but also identifies factors that have restricted the development of space science in China: the lack of long-term planning and stable funding support, the absence of a space science management organization, disagreements within China's space science community that have resulted in difficulties in choosing original projects, and limited international cooperation.