Abstract: Conception and mathematical model of factor analysis method are given and dimensionless optimization disposal is made on index data by using efficiency coefficient method. Accarding to KMO statistic and Bartlett sphere test results, sample data told is basically fitted to factar analysis: common factor value and common factor loading value are detemined through utlizing principal component analysis and SPSS 13.0 statistical analysis software. Physicochemical property test data from soil samples of 8 pipe sections along buried gathering pipeline in some oilfield are analyzed based on factor analysis method, and 6 physicochemical property test variables are composited into 2 common factors. Results display that the first stronger soil electrochemical properties factors on corrosion impact level of the pipeline successively is oxidation-reduction potential, chloride ion content, sulfate radical ion content and pH value, and the second one successively is soil resistivity and water content.