【Objective】The aim of the paper is to explore the anatomical structures and preventive measures of oleocellosis through researching the anatomical structure of two navel orange varieties from Chongqing’s Fengjie in different treatments and compare the effects of waxing or bagging on oleocellosis.【Method】 Plastics microtomy was used in this research through JB-4 permeating, embedding, and slicing with glass knife, double-staining by PAS-TBO, and peel cells and characteristics of organizational structure were observed and determined by microscope.【Result】No rupture was observed in oil cavities exist in the epicarp in the healthy or the early onset, but rupture was observed in late period in illness samples. The occurrence degree of oleocellosis related to the degree of uniformity of peel corneous layer rather than the thickness. Uniform texture, smooth appearance, good effect of retaining freshness, but waxing did not affect the occurrence of oleocellosis. Bagging lessened the chance of other disease infection, and the texture was uniform, the appearance was smooth, and the peel cuticle was more complete.【Conclusion】Strong light, external pressure, peel moisture and mechanical damage all could increase the probability of oleocellosis. Bagging may help to reduce the occurrence probability of oleocellosis.