In this study, heterocyclic anime (HCA) contents were monitored in commonly consumed pan-fried beefsteak based on the highest level of human exposure. Effect of addition of extra virgin olive oil (EVOO) on HCAs formation in fried beef steaks was evaluated. After EVOO was spread on the meat surface, the raw beef was cooked at $200^{circ}C$ for 5 min on each side. The HCAs were extracted from the meat samples and purified using a solid-phase extraction method and then analyzed by liquid chromatography-mass spectrometry (LC-MS). Among the 15 HCAs, 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b]indole (Trp-P-1), 3-amino-1-methyl-5H-pyrido [4,3-b]indole (Trp-P-2), 9Hpyrido [3,4-b]indole (Norharman), 1-methyl-9H-pyrido [3,4-b]indole (Harman), 2-amino-9H-pyrido [2,3-b]indole (A${alpha}$C), 2-amino-3-methyl-9H-pyrido [2,3-b]indole (MeA${alpha}$C), 2-amino-3,8-dimethylimidazo [4,5-f]-quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo [4,5-b]-pyridine (PhIP) were detected in all of the cooked beefsteaks. HCAs formation was significantly reduced (p<0.05) when the EVOO was added to the beef prior to cooking. The addition of 2 and 4 g of EVOO considerably inhibited HCAs formation in the fried beefsteak. However, adding excess amounts of EVOO promoted some HCAs formation.