The effects of N-acetyl-L-cysteine and 4-hexylresorcinol on browning inhibition of postharvest longan fruits cv. Daw were studied. The fruits were dipped for 5 min 5, 25, and 45 mM N-acetyl-L-cysteine and 0.01, 0.03 and 0.05% 4- hexylresorcinol, stored at 15+2°C and 85 %RH for 6 days. The results showed that N-acetyl-L-cysteine prevented pericarb browning of the fruits better than 4-hexylresorcinol, which resulted in better color values but did not significantly differ (p>0.05) among the concentrations used. Besides, the longan fruits treated with N-acetyl-L-cysteine tended to decrease disease incidence and lowered weight loss 2 compared with those treated with 4-hexylresorcinol. Neither browning inhibitor had an effect on the fall off fruits.