The present invention discloses a rapid detection method for fertilizer nutrients. According to the method, 1-5 mL of concentrated sulfuric acid is added during the sample digesting process, 0-2 mL of perchloric acid (or hydrogen peroxide) is added as a digestion agent, and the resulting digested solution requiring detection can be used for colorimetric determinations or turbidimetric determinations of nitrogen, phosphorus and potassium. The method of the present invention has advantages of wide application range, stable reagent, low cost, easy availability, short digestion time, complete digestion, convenient operation, high accuracy, time saving, labor saving, and the like. With the method of the present invention, the nitrogen content, the phosphorus content and the potassium content in the fertilizer can be rapidly and efficiently detected, such that the rapid detection requirements of the fertilizer sample during the fertilizer production process and the fertilizer sale process are met, and the purposes of time saving, labor saving, convenience, rapidness, accuracy and reliability are achieved.