The study was conducted in laoth house proceed to the Department of Horticulture and landscape design / College of Agriculture / University of Kirkuk, during the season (2013-2014) on Strawberry (Fragaria X ananassa Duch.) transplants, in order to study three factors, first was seaweed extract (sea force) in three levels (0,2 and 4 ml.l-1), the second was three potassium levels (0,2 and 4 gm .l -1),the third was two cultivars of strawberry (Fortuna &Festival) and the effect of interaction between the factors in the chemical characteristics of the leaves (the percentage of nitrogen, phosphorus and potassium) and qualitative traits (vitamin C content) and percentage of total acidity in the fruit).Resulted showed that’s spraying third extract sea force concentrations (4 ml. l-1) was significantly higher than the concentrations 0 and 2 ml.l-1 in the percentage of potassium and phosphorus in leaves ,the percentage vitamin (C) and total acidity in the fruit .Spraying the second concentration of sea force (2 m.l-1) was higher in the percentage of nitrogen and phosphorus .It has also showed that spraying potassium at the third concentration (4 gm.l-1) had significantly superiority in the percentage of nitrogen, phosphorus and potassium leaves , vitamin (C) and total acidity in the fruit, while spraying with potassium (2 gm.l-1)was superior in the percentage of nitrogen and phosphorus .Festiva cultivar showed significantly superior on the Fortuna cultivars in the percentage of major nutrients (nitrogen and potassium) in the leaves and vitamin (C) in the fruit, and did not vary varieties with each other in the percentage of phosphorus in the leaves and the total acidity in the fruit.