The purpose of this study was to investigate the antioxidant effects of non-fermented (CAC) and Monascus pilosus-fermented Columbia arabica coffee (FCAC), as well as Luwak coffee (LC) beans. The results indicated that total polyphenols content (mg/g of dry basis) was highest in CAC (70.69), followed by LC (62.07), and FCAC (41.38). However, the ratio of total flavonoids/polyphenols in FCAC was the highest. In terms of electron donating ability (%, coffee mg/mL), CAC was significantly higher than LC and FCAC. Regardless of fermentation, ferric reducing antioxidant powers were similar in CAC and FCAC and lowest in LC. LC also had the highest inhibitory activity against xanthine oxidase (XO). However FAAC had the highest inhibitory activity against aldehyde oxidase (AO), with nearly three times the levels found in CAC and LC. According to the above results, FCAC had a higher ratio of flavonoids/polyphenols and iron chelating activity than CAC. FCAC also had the highest AO inhibitory activity among the three experimental coffee beans. The results suggest that further studies are required to evaluate the bioactive components of various coffee beans so as to determine the potential benefits that coffee may have on preventing oxidative stress-related conditions.