Methods to determine total petroleum hydrocarbons in soil for the evaluation of contaminated level of oil have been studied. Extraction characteristics of several pretreatment methods were investigated and the practical detection limits for these methods obtained by gas chromatography/mass spectrometry were compared. The obtained results shows that the newly adopted pretreatment method which adopted mechanical shaking for extraction and used method for extraction solvent gives the lowest detection limit among the methods compared in this study are more parctical and applicable to real sample than the conventional methods. When this method was applied to the analysis of soil sample, the practical quantitation limit and relative standard deviation for gasoline, kerosene, fuel oil which are major sources of soil contamination, were found to be in the ranges of 2.5 - 10 ppm and 5 - 7 %.