Two field trials were carried out through 2019 and 2020 seasons to evaluate irrigation systems outcome  and potassium fertilization rates on water efficiencies, productivity, water-saving and financial return for potato crop (Solanum tuberosum L.) cv.“Sponta''. Eight transactions, two of the irrigation systems (surface irrigation & gated pipes technique), and three different rates of potassium fertilization (48, 96, and 144 kg K₂O fad^-1.) beside without adding potassium fertilizer were set in a split-plot design. Results indicated that sowing potato and irrigating it by the gated pipes irrigation system and using 96 kg K₂O of the potassium fertilization leads to an increase in productivity by 27.85 %, more water-saving about 25.33 % per year, recorded the maximum productivity of irrigation water and water productivity (6.76 and 10.01 kg m^-3, respectively), and also the topmost values of income, production, and the net return of irrigation water. Therefore, the economics of irrigation water turns out to be very essential for implementing irrigation management projects where farmers' over-irrigation traditions generally lead to low irrigation efficiency, waterlogging, and water losses. Therefore, the study recommends using the gated pipes technique with 96 kg K₂O fad^-1 under El Minia governorate circumstances and other corresponding conditions.