Tomato (Lycopersicon esculentum Mill) is one of the important commercial high value crops of Afghanistan. Among the different local varieties grown in Afghanistan, the “Pearson” variety is most popular because of its good commercial value due to its uniform globe shape and medium to large size. The study is conducted to understand the effects of different harvesting stages and postharvest treatments on the shelf life and postharvest quality of tomatoes (Pearson variety) stored under the Pusa Zero Energy Cool Chamber (ZECC) at the research farm of Agriculture Faculty, Kabul University. This is the first time that ZECC is introduced in Afghanistan for enhancing fruit shelf life. The standard dimension ZECC was built with 165 x 115 x 67.6 cm dimensions. After harvesting tomatoes at different maturity stages (Turning, Pink, and Light red color stages), fruits were precooled, graded, and treated with different concentrations of CaCl2 and mint leaf extract solutions. Thereafter, the tomatoes were placed in plastic baskets and stored in the Zero Energy Cool Chamber. During storage period, Total Soluble Solids (TSS, 0brix), pH, firmness (gr cm-2), shelf life, pericarp thickness (mm), fruit volume (cc), and fruit density were recorded. Two factorial CRD design was considered with harvesting stages as the first factor and postharvest treatments as the second factor. The data revealed that the shelf life of tomatoes was extended up to 29 days under T2 (turning color fruits treated with 6% CaCl2) and followed by T8 (turning color fruits treated with 6% CaCl2 + 6% mint Leaves extract) up to 28 days. Under T2, quality parameters such as TSS and pH increased from 3.85%brix and 2.85 to 4.4 0brix and 3.4, respectively. Firmness, pericarp and volume decreased from 1750 grcm-2, 0.75cm and 135 cc to 840 grcm-2, 0.67cm and 127 cc, respectively. At the last observation, density remained unchanged (1.00 gr/cc). In conclusion, tomatoes harvested at the turning-color stage treated with 6% CaCl2 and followed by 6% CaCl2 + 6% mint leaves’ extract had a significant effect on the enhancement of shelf life and quality of tomatoes under ZECC condition.