Abstract: The present study was carried out during 2009 and 201 0 seasons under aird environmental at the Research and Agricultural Experimental Station, King Saud University, Riyadh Saudi, Arabia in order to study the effect of putrescine (Put), gibberellic acid (GA]), Ascorbic acid (AA), Ethrel (Eth), salicylic acid (SA), cytofex (CPPU) and calcium chloride (CaC12) at two stages of berry ... [Show full abstract] development pea stage (5 - 7 mm fruitlet diameter) and veraison stage (when approximately 10% of the berries on 50% of the clusters had softened and red color) on yield and fruit postharvest physico-chemical quality characters at commercial harvest day often years old Flame seedless grapevine cultivar. Vine yield increased by spraying Put, GA], SA, CaC12 and Cf'Pl.I, Berry weight, length and width increased by Put, GAJ and CPPU application. Berry firmness and adherence strength were increased by all sprayed substances, except AA and Eth. The berries quality grade (marketable) increased by all sprayed compounds except AA. On the other side, the Eth decreased the harvest period. The Put, GA] and CPPU treatments increased berries acidity percent as well as they extended the harvest period as compared with Eht. In general all sprayed compounds improved cluster and berry physic-chemical characters.