To investigate the effects of potassium (K) and boron (B) applied as nanofertilizers on 'Medjool' date palm productivity and fruit quality, a field experiment was conducted during the 2022 and 2023 seasons. The experiment involved twelve-year-old 'Medjool' date palms grown in newly reclaimed desert lands. Three concentrations from nano-potassium (100, 200 and 300 ppm) and nano boron (10, 20 and 30 ppm) were examined either individually or both element in combinations. The study included 10 treatments from nano-K, nano-B, nano K + nano-B in combination, and mineral K and B (control). The obtained data showed that, spraying nano-K or/and nano-B at different concentrations significantly enhanced fruit set %, fruit retention %, (g) and bunch weight (kg) and contrary decreased fruit drooping %. Both nano-K and nano-B were highly effective in improving all fruit physical properties (i.e. fruit weight(g), fruit dimensions(cm), pulp weight(g) and pulp: seed ratio). Furthermore, the chemical properties (i.e. total soluble solids (TSS%), reducing sugars, non-reducing sugars and total sugars) of Medjool dates was significantly increased as a result of replaced the traditional mineral K and B by using nano-K and nano-B fertilizers. Conversely, total soluble tannins % and total crude fiber were significantly decreased. In addition, the combined application of nano-K and nano-B showed a marked superiority rather than using each one individually. However, the palms sprayed with nano-K at 300 ppm and nano-boron at 30 ppm in combination present the best results in term of fruit set, fruit retention, yield, fruit physical and fruit chemical properties.