Abstract: The kinds of organic pollutant of different sampling periods in Songhua River's water have been analyzed by GC/MS method. The preparation courses of the sample and determination's condition were discussed. The results indicate that in three sampling period, the kinds of organic pollutant are the most in medium water period, the least in low water period. the kind of polycyclic aromatic hydrocarbons was influenced most by sampling period, the kind of substitute benzenes went next, The kind of phthalate esters slightly. the experiment results are significant to protect environment and people's health.