Abstract: Thiabendazole, sodium carbonate, hot water and Thyme extract are among the serious chemical compounds which seem to be used as treatments of the fruits in the warehouses. But the effects that each one has for this purpose is different. Moreover it seems that the size factor also influence the qualitative and quantitative characteristics of the fruits. In order to study the effects of these different treatments on longevity of Valencia orange storage a survey, in the form of entirely random districts with 19 treatments and two sizes of the fruit (5/5 to 6 cm and 6/5 to more than7cm), is conducted. After making the treatments prepared and putting them in the plastic bags, fruits are kept in a usual warehouse with 20-28 c about 80 days. Base on the results, the most quantity of decay is observed through treatment control2 for about 49/035 percent and the least quantity relates to treatment Sahed1, hot water and Thyme extract. The fruits grouped as size 1 (5-6/5cm) showed the highest level of decay for about 36/62 percent. The highest quantity of losing weightwas observed through treatment control 2 about 11 grams and the lowest showed by treatment control 1, hot water and Thyme extract. The fruits in size 1 had the highest quantity of losing weight about 7/75 grams. Treatmentcontrol1 with 4/172 showed the highest level of PH for the extract of fruit. The fruits grouped as size 2 (6/5-7cm) had 3/86 pH. while they didn’t have meaningful differences with other treatments, Thyme extract (1000) and rosemary extract (2048), hot water and rosemary extract (1024) , hot water and rosemary extract (256) parts in million 1/034,1/035,1/035 kg/cm2respectively had the highest level of density. Considering this issue, the highest level of density belonged to fruits in size1 (5-6/5cm) that was 1/037kg/cm2.In conclusion, it is inferred from this study that treatments control 1 (free from treatment and unvaccinated) and hot water and thyme extract, in comparison with other treatments, were more successful base on the observed results. In addition, it can be concluded that as they have lower rate of decay, fruits with higher size have more resistance for storage in the warehouses. So with careful attention to environmental issues and producing organic products, it is recommended to use herbal treatments instead of chemical treatments.