Tomato fruits (Lycopersicon esculentum cv. Momotaro) at turning stage were treated by hot air at 38℃ for various exposure times from 6 hrs to 6 days and then stored at 20℃ for ripening. The weight loss, total sugar, titratable acidity and firmness were measured at the red-ripe stage as well as the subsequent 3 and 6 days. The surface color development was delayed in fruits exposed to hot air for 1 day or over, and the extent of delay was enhanced with an increase in exposure time. Ethylene production was inhibited during hot air treatment and recovered after transfer to 20℃. A significantly high weight loss was observed in fruits exposed to hot air for 2 or more days, but did not affect the external quality. Total sugar, titratable acidity and firmness of fruits treated for up to 3 days were similar to those of the control. The hot air treatments for duration of 1 to 3 days were found to be effective in delaying the ripening and maintaining the quality of tomato fruits. Such treatments would be usefully applied in the postharvest quality management of tomato fruits.