ABSTRACT: This study was concerned with potato tubers in the experimental farm of Faculty of Agriculture, Menoufia University during the season 2020. The main objective of this work is to study the effect of with organic fertilizers comparing with using mineral fertilizers on some physical and mechanical   properties of potato tubers during storage period. The experiments were conducted on two varieties of potatoes, (Diamond and Arizona). Two types of fertilizers were used in the cultivation of potato tubers, which were organic fertilizers and mineral fertilizers. The experimental treatments were divided into five treatments as follows: Control (without fertilizers) (T1) - 100% mineral fertilizer (T2) - 50% mineral fertilizer and 50% organic fertilizer (T3) - 25% mineral fertilizer and 75% organic fertilizer (T4) - 100% organic fertilizer (T5). The potato tubers stored at 4°C for 45 days. The reported results showed that, the best physical characteristics of potato tuber were found with fertilization treatment of (50% organic 50% mineral). Significantly found best among all treatments successive growth stages in term of maximum average weight (114 g), Shape index (331.30 %) and coefficient of friction with wood after 45 days of storage (.561). Where, the highest average value potato tubers firmness treatment (75% organic 25% mineral) is (114N).