The tomato ( Lycopersicon esculentum) is one of the most widely consumed fresh vegetable in the industrialized world. Tomatoes are a rich source of fibre , vitamin A, C, and lycopene and studies indicate that have important role in human nutrition. Due to high perishability of tomato, it cannot be stored for long duration ut by means of postharvest technologies 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 tomato fruit cv. "Dafnis". The first experiment was conducted to asses the age of storage life of tomato 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 10 °C and 90% for 35 days. After that the fruits were gotten out each 7 days and were assesed to determine parameters such as titratable acid, pH, soluble solids, vitamin C, firmness, weight loss and lycopene content. 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 and were tested at intervals of every 4 days. Both of experiments were performed as a split plot design in time in a complete randomized design with three replications.The results of the first experiment showed that calcium, has a significant effect on measured indexes. The results showed that The lowest pH, soluble solids, lycopene, the highest titratable acid and vitamin C in the %1 calcium ascorbate were recorded which it had significant difference from the other treatments. The highest amount of firmness was recorded with %1 calcium ascorbate and %2 calcium choloride which they had no significant difference to each other. The lowest weight loss was recorded at the %1 calcium ascorbate and except with %2 calcium choloride it had significant difference to other treatments. The results of the second experiment showed that treatments calcium, had a significant effects on all measured indexes. The lowest lycopene content was recorded at the %1 calcium ascorbate and except with %2 calcium choloride it to had significant difference to other treatments. The results showed that The lowest pH, soluble solids, the highest titratable acid and vitamin C in the %1 calcium ascorbate were recorded which it had significant difference from the other treatments. The effect of time on all measured traits was significant in each two experiments. The interaction effect of treatment and time was significent about all charactristics. According to the result of this study, treated fruits with %1 calcium ascorbate and calcium choloride cause maintain fruit quality properties during storage period. Key Words: tomato, postharvest, calcium ascorbate, calcium choloride, nano chelate calcium.