This work was carried out during two successive seasons of 2011 and 2012 to evaluate the effect of some natural postharvest treatments i.e. thyme and clove oils at 2 and 3% on some fruit quality parameters of Washington navel orange fruits under cold storage (5±2˚C& 90% R.H.). Briefly, fruit weight loss %, decay %, T.S.S % and respiration rate (ml CO2/kg fruits/hr) of Washington navel orange fruits were increased in most cases with prolonging the storage period. Whereas, total acidity % and ascorbic acid (mg/100 ml juice) were decreased with advancing the storage period. However, the lowest values of weight loss %, decay % and respiration rate as well as the best results of shelf life (days) ,besides the highest values of total acidity % and ascorbic acid were gained by 3% clove oil treatment.