The sweet bell pepper( Capsicum annum ) is one of the most widely consumed fresh vegetable in the industrialized world. Due to high perishability of bell pepper, it cannot be stored for long duration ut by means of postharvest technologies the somewhat can control their decay. Calcium as an essential plant nutrient actively participates in cell wall structure also as a secondary messenger that plays central role i regulate physiological function in fruits, vegetables and flowers during postharvest life. It seems calcium is good resources to preserve agricultural crops. The current experiment was conducted to find the effect of calcium on postharvest life of sweet bell pepper fruit cv. "Torento". The first experiment was conducted to asses the age of storage life of sweet bell pepper using treatments of calcium choloride (%1, %1.5, %2), calcium ascorbate (%0.25, %0.5, %1) and nano chelate calcium (%2, %4,%6). After treatment, the fruits were presereved at an incubator with 8 °C and 90% for 35 days. Then the fruits were gotten out each 7 days and were assesed to determine parameters such as titratable acid, pH, soluble solids, vitamin C, firmness and weight loss . Antioxidant activity and total phenolic compound were elucidated in 21,28 and 35 days of storage period. The second experiment was done similar to the first experiment for evaluating the shelf life except the fruit after treatment, were kept in an incubator with 18 °C , were tested at intervals of every 4 days and the activities of antioxidant enzymes such as proxidase (POD), catalase ( CAT ) and ascorbic acid oxidase (AAO) were elucidated in the fruits of experimental sets and they were compared with that of control set in 15 and 25 days of storage period. Both of experiments were performed as a split plot design in time in a complete randomized design with three replications. The results of first experiment showed that the lowest percentage of weight loss, pH and total soluble solids, the highest firmness and titrable acidity, was recorded by the NanoCa 6%. The highest antioxidant activity was in CaCl 2 2% treatment. The highest content of total phenolic compound and the lowest content of cartenoeid was recorded by CaAsc1%. Treatments have not significant effect on clorophyl content and vitamin C. The results of secoud experiment showed that the lowest percentage of weight loss, the highest pH, antioxidant activity, clorophyl content ,enzymatic activity of peroxidase and catalase was recorded by NanoCa6% treatment. The lowest activity of ascorbic acid oxidase enzyme was in CaCl 2 2% treatment. The highest firmness, vitamin c, total phenolic compounds and the lowest TSS was in CaAsc1% treatment. Treatments have not significant effect on titrable acidity of sweet bell pepper fruits stored in 18?C. According to the result of this study, treated fruits with %1 calcium ascorbate , 2% ofcalcium choloride and 6% of nano chelate calcium cause maintain fruit quality properties during both the storage conditions (18 ?C and 10 ?C). Key Words: bell pepper, postharvest, Calcium ascorbate, Calcium chloride, Nano chlate Calcium