A field experiment was carried out at newly reclaimed land at El-Wady Co: Farm West of Wady El-Natron, El- Bohera Governorate, Egypt during the summer season of 2015 to evaluate the effect of different levels of mineral potassium sulphate and natural rock K and their combination under some bio-activators (without addition of bioactivators, with silicate dissolving bacteria and 10 ton compost/fed) on potato plant. The results reveal that increasing potassium level improved all of the studied growth parameter (shoots fresh and dry weights/plant), yield components (number of tubers/plant and mean tuber weight), yields (shoots and tuber fresh and dry yields ton/fed) and N, P and K uptake in tuber and shoots. Addition of feldspar enhanced all of the studied growth paramters, yield and its components and  N P K uptake, Combination of 75% of the recmmonded rate of potassium sulphate with 25% feldspar gave all of the studied quality and quantity parameters equal to those obtained under 100% potassium sulphate. Bio-activators enhanced all of the abovementioned studied parameters. Compost was more effective than silicate dissolving bacteria in its effect on potato quality and quantity. The treatment of 75% of the recommended rate of potassium sulphate + 25% feldspar + 10 ton/fed compostgave the highest values of potato quality and quantity parameters.