Performance of the palm trees and fruit quality of cv. Zaghloul under different levels of natural potassium (NP) resource (K₂O 10 %) individually or in combination with potassium soluble bacteria (KSB) were studied in the 2016 and 2017 seasons. Treatments included 3, 6 or 9 kg/palm per year of NP either individually or in combination with KSB on ‘Zaghloul' date palms grown on sandy soil with 7 meters apart under surface irrigation system; whereas, palms received 2 kg/palm per year potassium sulfate (50% K) served as the control. The results revealed that 9 kg of NP in combination with KSB enhanced vegetative growth, pinnae mineral content, chlorophyll, bunch weight, palm yield and fruit quality than other applications or control palms. Therefore it is recommended to use 9 kg of NP in combination with KSB/palm/year for increasing yield of Zaghlol date palms and improving fruit quality.