The button mushroom ( Agaricus bisporus ) is full rich food in nutrient and benefit due to feeding, so that cultivatio of this vegtable is common for years. There are about 2000 species of edible mushroom from 14000 existing species. Amang them, three varieties named Agaricu bisporus , Pleurotus and Lentinus edodes have become more commercial use. compared with fruits and vegetables, mushroom has a higher respiration rate and due to the lack of protective layer to prevent water loss, spoilage accurs quickly, thus decrease the shelf life and storage life of mushroom for distrubiotion and supply is limited. Storage life of fresh mushrooms at common temperature varie between 1to 3 days and at 4 ° C varies between 4 to 7 days. The mushrooms with 5-10% of the weight loss began to be dried up un available to use. Therefore, due to difficultie in distributio and supplyfresh mushroom market , postharvest physiology require futher study. . It seems that suitable coating film for the mushroom after harvesting and for its commercial is the best option . Also appication of chitosan as a coating agent in order to adjust the respiration of crop, physiological diseases and microbial growth were use. This recently research was achieved to find the best coating film and chitosan concentration to increase the storage life and decrease the postharvest losses. In first research , the treatment were: shahed as an ordinary package (Selefon) and 5 tapes of coated films (PE (Poly Ethylene with 40 and 65 micron thickness)، BOPP (Biaxially Oriented Polypropylen with 25, 35 and 40 micron thickness) ،CPP (Cast PolyPropylen with 25 and 40 micron thickness)، PET (Poly Ester with 12 and 24 micron thickness and ( PVT (Polyvinyl Chlorid (with 30 micron thickness at 10, 15, 20 and 25 days of storage at 1°C and humidity of 90 % was performed in 3 replication. After each storage period, the mushroom were evaluated in terms of some physical and chemical properties. the second research , after selecting of the best coating film, mushroom were treated with four concentrationof chitosan(0 , 0.5, 1 and 2 percent) and the assessments were achived similar to first research. First study wase arranged as split plot design. The second study was arranged as split plot-factorial. The resuls of the first research showed significant effect of all types of plastic coating measerments on the level of one percent probability. The research showed that the highest firmness value, Soluble Solid Content(SSC), organic acid, acidite(pH), and lowest weight less and decay were observed in packet mushroom with the coating film : BOPP and CPP and the lowest amounts was recorded in the fruits packed with shahed, PVC, PET and PE. Mushroom fruits Packet with PE coating film, showed the best color index during the storage period. The effect of time on all of the measured during the storage period, was significant. The interaction between time period and coating film in terms of firmness and Soluble Solid Content(SSC) were significant. The resuls of second research showed that chitosan had a significant effect on all measured characteristics at one percent level of probability only Soluble Solid Content(SSC). The result showed that the highest firmness, organic acid, acidite(pH), and lowest weight less and decay were observed in treatment mushrooms packed with 2% chitosan and the lowest above mentioned was recorded in treatment mushroom packed without chitosan. Different concentration of chitosan in the case of decay index did not show significantl difference. The effect of time on all traits were significant. The Interaction between film coating and Chitosan in terms of weight loss, Soluble Solid Content(SSC) and decay indices was significant. The Interaction between the film coating and Chitosan and time period was significant only index weight loss. According to result of this study, coating film(BOPP35?) was suggested.