: In order to investigate the effect of Zn plus Mn foliar application on the performance and quality of three commercially cultivated potato cultivars, a field experiment was carried out in 2005/2006 and 2006/2007 cropp-ing seasons, in the Vegetables Crops Experimental Farm, Faculty of Agriculture, Assiut University. The cultivars used were ''Spunta'', ''Diamant'' and ''Cara''. Combined Zn and Mn foliar application (ZnSO₄ and MnSO₄) was used (1.5g/L each) at three different frequency levels, twice/week, once/week and once/2 weeks. The tested cultivars significantly differed in most of the studied traits. The cultivar ''Spunta'' produced the highest number and size of marketable tubers, and total marketable yield in both seasons. Application of Zn plus Mn foliar combination one time every two weeks significantly increased the number and size of marketable tubers and total marketable tubers. The highest yield of marketable tubers (ton/ha)* was recorded for ''Spunta'' cultivar when treated with Zn plus Mn foliar combination every two weeks.