Levels of mineral hydrocarbons which have migrated from wax coatings into cheese have been determined for 20 retail samples using a gas Chromatographic procedure. Contamination was limited to the outermost 2 mm of cheese in direct contact with the wax where levels of hydrocarbons were found to range from 10 to 150 mg/kg. On a whole cheese weight basis these amounted to < 1 to 27 mg/kg (<0·2 to 3 mg/dm2contact area). Components attributed to hydrocarbons in cheese samples remote from the waxed surface (background levels) were typically 3–5 mg/kg. Background levels were subtracted from the results for surface samples to obtain migration values. There was evidence that the surface contamination of cheese with mineral hydrocarbons occurred by a combination of diffusion into the cheese and adhesion of wax components onto its surface.