© 2018 International Society for Horticultural Science. All rights reserved. This study investigated the effect of calcium-boron contration on the development and improvement of quality on postharvest mango cultivar ‘Mahachanok’ by spraying 40% calcium (Ca) and 0.3% boron (B) solution at 1, 2, 3, and 4 mL L -1 concentration, and the spraying times were 60 and 90 days after anthesis (compared with water as a control). Thereafter, uniform and non-defected mango fruits were harvested at 110 days after anthesis and stored at 15°C. The chemical and physical properties were determined every 3 days. The results showed that the 1 mL L-1 concentration Ca-B sprayed mangoes which were kept at 15°C could have their shelf life extended for 24 days; due to the % titratable acidity and the vitamin C content, the firmness was higher than other achieved in other treatments. It was also found that the TSS, L*, a*, and b* values of the peel were less than those obtained from other treatments. Additionally, the application of Ca-B was found to reduce the activity of pectin methylesterase and polygalacturonase which caused delay in the ripening of the mango fruit.