This study is to identify the factors affecting the intrinsic motivation of the university students in Hong Kong. The factors of curiosity and external regulation with intrinsic motivation are taken into investigation in this study because it is found that the relationships between these factors and intrinsic motivation of the local university students have seldom been examined. This study adopting a survey of 137 sampled students was conducted in a local university in 2011. Findings showed that students with curiosity could stimulate their higher intrinsic motivation; but external regulation was not found to be related to intrinsic motivation.