This research was conducted in a private Banana farm at Al-Kornea'a, Abyan Governorate to determie proper concentration of Ethephone, the active ingridient of Ethyrel hormone, that can be injected into the Banana bunches for friuts ripening in a temperature controlled room adjusted at 19oC± 1o without using any ripening materials in the ripening room. Three concentrations "Ethephone" (500, 750 and 1000ppm) were tested. Three Banana bunches were injected from each concentration by a robust injector with a needle of wide opening. Results indicated that the concentration of 1000ppm significantly gave an even ripening of Banana fruits, that harvested the next day after field injection and packed in plastic boxes lined with polyethylene transparant bags and left for 5 days at 19oC ± 1o. This treatment gave 100% ripe fruits per box with a colour stage of 5 which is preferred by consumers. The total soluble solids reached 12.5% that gave the fruits a pleasant flavour and a sugary taste direct from the cold room. The control, and the 500ppm., and 750ppm treatments gave uneven fruit ripening that reached 0, 30 and 75%; where as a T.S.S. of 4% 5.6% and 8.5% were found per box respectively.

Key Words :Ethyrel, Ethephone, Hormone, Bunches, Banana, Ripening