The distribution of n-alkanes, isoprenanes, and adamantanes in biodegraded and nonbiodegraded condensates (of types B and A by Al.A. Petrov's classification, respectively) of different genotypes has been studied by gas-liquid chromatography (GLC) and gas chromatography-mass spectrometry (GC-MS). It has been shown that the biodegradation does not affect the relative distribution of adamantanes in the condensates.