Based on monitoring data of 21 sections of Sihe River in October 2013,the average comprehensive pollution index( Pj) was adopted for water quality evaluation,heavy pollution monitoring site selection and pollution source analysis. The results showed that Pjof all monitoring sections was 2. 9( > 2),among which,the percentage of heavily polluted sections( Pj> 2) was 76. 2%. The average value of individual soiled contribution rates of TN and TP of those sections were 97. 4% and 65. 8% respectively,indicating t...