Mobile Web search engines as well as Fixed ones will become much more important for our Web access in the near future. However, mobile computing environments have troublesome limitations, as compared with traditional desktop computing environments. In order to solve the so-called "mismatched query problem" due to more shortness and ambiguity of mobile users? original queries, this paper proposes a novel method for context-aware query refinement based on their current geographic location and real-world contexts which are inferred from the place-names representing the location and the Web as a knowledge database.