Abstract: External contamination of Space Station have been studied in some developed countries since 1970s. Up to middle 1990s, external contamination control system including analysis, simulation, validation experiments as well as design has come into being and been used for building the International Space Station. This paper summarizes the classification, the effect, the analysis and the control requirements of external contamination of space station based on literature search. Suggestions with regard to external contamination researches in China are also presented for the purpose of serving building of China's space station.