To investigate the effect of ascorbic acid and chitosanon the postharvest life of button mushroom (Agaricus bisporus), an experiment was conducted based on a completely randomized design with three replications. The treatments were grouped in ascorbic acid (0, 1.5, and 3 mM) and chitosan (0, 0.25, and 0.5%) levels and their interaction. At the end of the experiment, the nutritional value including Vitamin C, total soluble solids, total acidity, Phenol and antioxidant activity in button mushroom were recorded. The results stated that the maximum levels of all traits were obtained in response to use ‘1.5 mM ascorbic acid + 0.5% chitosan. The minimum percentage of weight loss was observed at 3 mM ascorbic acid + 0.25% chitosan at 12th days and maximum value belongs to control treatment. Delaying of senescence and increasing of the nutritional value of button mushrooms in response to the association of these materials with molecules and prevention of their breakdown. The highest shelf life equivalent to 14.6 days was in 5‘1.5 mM ascorbic acid + 0.25% chitosan’ treatment that caused an increase of 8 days in comparison with control. It can be said that the application of treatments in the post-harvest stage has more influence on the nutritional value and durability of button mushroom. پرونده مقاله