This study investigated the inhibitory effects of p-coumaric acid, ferulic acid and feruloylated oligosaccharides on catalytic activities of tyrosinase by analysising tyrosinase steady state activity and enzyme kinetics. The results showed that the three compounds were found to efficiently inhibit tyrosinase monophenolase activities. The p-Coumaric acid was the strongest inhibitor followed by feruloylated oligosaccharides and ferulic acid, with the IC₅₀ value of 0.75, 3.20, 9.30 mmol/L respectively. Moreover, p-coumaric acid and ferulic acid were found to inhibit the activities of diphenolase with IC₅₀ value of 4.3, 12.7 mmol/L respectively; however, feruloylated oligosaccharides showed no inhibitory effect on diphenolase activity. p-Coumaric acid increased the lag time of monophenolase activity, but ferulic acid showed little effect; while feruloylated oligosaccharides reduced the lag time of monophenolase activity. Enzyme kinetics analysis indicated that p-coumaric acid is a competitive inhibitor of the monophenolase, while ferulic acid and feruloylated oligosaccharides showed a mixed inhibitory effect.