Phytoremediation of petroleum hydrocarbons from soil is a promising approach because of its low cost and environmentally friendly nature. This work intends to contribute to this area by investigating the potentials of common forage legumes, red clover (Trifolium pratense L.) and white clover (Trifolium repens L.), for petroleum oil phytoremediation. Five different cultivars of red clover (Namuq, 79, 818, Lakeland, 1881) and 3 cultivars of white clover (361, 453, 455) were used to evaluate intra- and interspecific variability in terms of their phytoremediative potential. The seeds were germinated in soil mixed with 1, 5 and 7% (v/v) Siberian light crude oil (SBL), and the seedlings were grown for 30 days at the same media. Germination ratio (%), stem length, number and width of leaves were used as physiological parameters for pre-evaluation of plantlets for oil tolerance. It was shown that white clover is not tolerant to oil contamination, whereas red clover can prevail up to 7% of crude oil application despite the significant decrease in the biomass. The most tolerant cultivar of red clover was Lakeland. Aliphatic hydrocarbon fingerprints observed in the GC-MS chromatograms of leaf extracts pointed out this cultivar as a valuable source of information for understanding the tolerance mechanism of plants to hydrocarbons.