The solubility and sorption of oil by uncontaminated clay loam and silt loam soils were studied from water and cosolvent/watersolutions using batch techniques. The data obtained from the dissolution and sorption experinaents were used to evaluate theapplicability of the cosolvent theory to oil as a complex mixture. Aqueous solubility and soil-water distribution coefficients (Kd,w,L/kg) were estimated by extrapolating from cosolvent data, with a log-linear cosolvency model, to the volume fraction of cosolvent(fc) 0, and were compared with direct aqueous measurements. The extrapolated water solubility was 3.16 mg/L, in good agreementwith the directly measured value of 3.83 mg/L. Extrapolated values of Kd,w for the two soils were close to each other but consistentlyhigher than the values from direct aqueous measurements, because of the presence of dissolved organic carbon (DOC). The partitioncoefficient (KDOC) between the DOC and the reely dissolved phase and the OC-normalized sorption coefficient (KOC) were determined.The average values of logKDOC and logKoc were estimated as 4.34 and 3.32, respectively, giving insight into the possibility of oilbecoming mobilized and/or of the soil being remedied. This study revealed that the cosolvency model can be applied to a broader rangeof hydrophobic organic chemicals (HOCs) than has been previously thought. The results aided in a reliable determination of watersolubility and sorption coefficients and provide information about the fate of oil in solvent-contaminated environment.