Table grapes are one of the most consumed non-climacteric fruits globally, and practices for their quality are socioeconomically important. In this study, the effects of the combined and separate applications of two plant activators Ortho Silicon (Si, Optysil, 0.5 mL L-1) and Ascophyllum nodosum-based seaweed extract (ANE, KelpGreen 2.5 ml L-1) were tested by two applications after fruit set 15 days intervals to table grapes cvs. Gök Üzüm and Müşküle in a producer vineyard at Hadim town of Konya province in middle Anatolia37°2'15"N 32°34'53" E, 1060 m above sea level. The effects of the applications on ripening, cluster and berry characteristics and post harvest shelf life during 10 days of storage at room conditions were analyzed. Both plant activators provided an increase in cluster size and an improvement in ripening. Si+ANE was more effective on the maturation and quality retention during the post-harvest shelf-life period. All applications provided reduction in weight loss (WL), decay rate and berry dullness, and it reduced berry separation force due to the drying of the peduncle and decreased the maturity index (MI) increase in the post harvest period. Thus, it contributed to the formation and retention of fruit quality. According to the data obtained from this study, improvements in the sustainable preservation of table grape quality can be achieved by applying Ortho Silicon and A. nodosum based seaweed extract separately and together between after fruit set and before veraison.