Abstract: Background and Objective: Cultivation of ‘Costata’ persimmon has been increasing in Egypt due to the increasing consumption of the fruit having a distinctive taste. The main problem is June drop and pre-harvest fruit drop, especially because that ‘Costata’ persimmon is a parthenocarpic cultivar, subsequently, the fruit yield and quality is not economical. Therefore, improving yield and fruit quality is a major goal and could be achieved by using fertilization and rootstocks. Materials and Methods: This investigation conducted during two consecutive seasons 2018/2019 on ‘Costata’ (Diospyros kaki) persimmons, grafted onto D. kaki and D. lotus seedlings, grown in a private orchard at El-Tarh region. A split-plot design had performed. ANOVA test were used to compare the samples of different treatments. Results: ‘Costata’ persimmon trees grafted onto D. kaki had higher shoot length, fruit set, fruit retention, yield and leaf nitrogen in the first season and calcium content as compared with the trees grafted onto D. lotus. Potassium fertilization increased shoot length, fruit set, fruit retention, yield, fruit weight, Total Soluble Solids (TSS) (%), total sugars, carotenoids. It also increased leaf potassium, magnesium, zinc, manganese, iron and phosphorus content in the second season, whereas tannins, acidity and calcium content decreased. Conclusion: It is concluded that potassium fertilization at 1000 g/tree was more effective application for the persimmon trees grafted on D. kaki which is a better choice for more shoot growth, fruit set and retention (%), yield and fruit weight compared with the trees grafted on D. lotus. However, the trees grafted on D. lotus have fruits with more quality.