Investigation of contaminated soils, assessment of treatment processes and environmental monitoring of remediated soils require screening many samples. Laboratory analyses (gaz or liquid chromatography) are expensive and time consuming. Moreover, the procedures are not suited to field conditions. In this context, a new field kit for PAH diagnosis has been developed. Based on the UV spectrophotometric analysis of a soil organic extract, the total PAH estimation, in reference to the 16 PAHs included in the US Environmental Protection Agency Priority Pollutants List, can be obtained on site within 20 minutes. Moreover, a “treatability index”, informing on the potential degradation of pollutants which may occur into the soil, is given. This last is connected with the proportion of PAH including two or three cycles in their structure (“light PAHs”) which are known to be more readily biodegradable. A validation on several contaminated soil samples, from different origins, has been carried out. This tool allows to give a rapid diagnosis of total PAHs concentration in a contaminated soil and to point out the most polluted areas on an industrial site. The proposed kit is well fitted for the monitoring of a treatment process and the survey of natural attenuation into a PAH contaminated soil.