The petroleum pollutants in soil can be rapidly detected with laser induced fluorescence technique. However, the fluorescence emission characteristic of each pollutant would be different under different soil physical properties. In order to prepare suitable soil samples rapidly in the field, the relationship between fluorescence intensity and spectral stability of soil organic pollutants, soil bulkiness, particle size and moisture was studied in this paper. The stability of the fluorescence spectra of the soil samples was better when the pressure was greater than 2 MPa, and the relative standard deviation of the fluorescence intensity of the nine soil samples with different porosity was 3.51%. The fluorescence intensity difference of the oil soil samples with different particle sizes was small, and the fluorescence spectrum RSD of 100-mesh soil samples was 2.25%. The results shows that the fluorescence spectrum is stable when the surface of the soil sample is flat and clean. The bulkiness and particle size of soil have little influence on fluorescence emission. When the soil moisture is less than 10%, the changes of fluorescence intensity is less significant , but when the humidity range is greater than 10%, the fluorescence intensity changes greatly. This paper provides references for the rapid and effective pretreatment and accurate measurement of petroleum contaminated soil samples in the field.