The effect of modified atmosphere packaging (MAP) on headspace volatile compounds of raw ground beef, as profiled by solid phase microextraction (SPME), was studied. Raw ground beef patties (81:19 lean:fat) were packaged in high oxygen MAP (80% O2, 20% CO2) or carbon monoxide MAP (COMAP) (69.6% N2, 0.4% CO, and 30% CO2) atmospheres. Packages were stored at 22 °C under continuous fluorescent lighting (1530 lux). Package headspace was sampled over a three consecutive day trial by SPME and then analyzed by gas chromatography/mass spectrometry. In total, 20 volatile compounds were separately identified in the headspace of COMAP and high oxygen MAP packages; the progression of time evidenced development of known spoilage-associated compounds including several hydrocarbons and hexanal. The identification of compounds in similar relative abundance in both package types suggest their development via alternative oxidation and non-oxidation pathways.