Nutrient elements are essential for plant growth and development，and the coordination of nitrogen，potassium and calcium nutrition helps to improve crop yield and quality. If the nitrogen，potassium and calcium nutrition can be coordinated，the yield and quality of cassava can be further improved，which has important guiding significance for high yield and high quality of cassava. SC9 edible cassava variety was used as material，red soil: vermiculite=1: 2 was used as the test cultivation medium，orthogonal experiment of three factors(nitrogen，potassium and calcium)and two levels(1 is high level，2 is low level)was designed in pot culture. Nitrogen，potassium and calcium were applied at 100 days(rapid growth stage)and 210 days(root enlargement stage). The differences of photosynthetic rate，root tuber yield，total plant biomass，root tuber nutrient content and quality under different treatments were analyzed. The results showed that:nitrogen，potassium and calcium fertilizers had significant effects on the agronomic characters，root nutrient content and root quality of cassava. For the growth and development of cassava，the interaction of high nitrogen and high potassium promoted the photosynthetic rate of leaves under low calcium coordination. For the yield of cassava root，high potassium and high calcium interaction treatment significantly increased the total biomass of cassava plant；low nitrogen level significantly promoted tuber yield of cassava；nitrogen，potassium and calcium elements and their interaction had significant effects on the nutrient content of cassava root tuber，high calcium or low nitrogen levels significantly promoted potassium content in root tuber. In terms of quality，the contents of total sugar and protein in root tuber were significantly increased by low nitrogen level；application of high potassium increased the total sugar content of root tuber；low calcium increased protein content in root tuber. Therefore，the application of cassava fertilizer should focus on reducing the input of nitrogen fertilizer and applying it in a proper proportion with potassium and calcium fertilizer，so as to achieve high yield and high quality effects. In conclusion，lack or excess of nitrogen，potassium or calcium，as well as relative imbalance，are not conducive to the growth and development of cassava，so it is necessary to pay attention to a reasonable proportion of application to maximize the function of elements. According to the data analysis，the optimal fertilizer application amount of cassava pot is application of nitrogen 0.280 g/kg，potassium 0.210 g/kg or 0.420 g/kg，calcium 0.165 g/kg. Under such combination fertilizer application，the yield of edible cassava was relatively higher and the root quality was better.