The invention relates to the technical field of crop fertilization, in particular to a quantitative potassium application and phosphorus application method based on soil rapid available potassium/rapid available phosphorus. According to the method, potassium application and phosphorus application quantity is determined by building a fertilization model based on nutrient conversion rate. The potassium application and phosphorus application model is determined by the mode: (1) determining potassium application and phosphorus application conversion rate; (2) determining potassium application andphosphorus application quantity regulating proportions B and L of a land parcel; (3) determining the ecological and economical potassium application and phosphorus application model. According to thequantitative potassium application and phosphorus application method based on soil rapid available potassium/rapid available phosphorus, the optimal potassium application and phosphorus application quantity of an area and the land parcel can be determined only according to area high-yield soil available potassium/available phosphorus proportions and soil potassium and phosphorus content, quantitative fertilization is simple and practical, potassium and phosphorus can be quantitatively applied according to the area or the land parcel, on the premise of ensuring per unit yield and quality, fertilization economic benefits and fertilizer increasing soil are increased, and fertilizer non-point source pollution is reduced.