The invention discloses a rapid detection method of nifedipine in blood pressure reducing health foods, and a detection card developing method. The detection method comprises the following steps: 1, immersing a sample to be detected in an extract agent A and an extract liquid B, oscillating, and standing to extract nifedipine; 2, taking the obtained immersion solution, and filtering the immersion solution through a micro-porous filter membrane; 3, taking a certain amount of the obtained filtrate, and adding a sample dilution solution C according to a volume ratio of the sample dilution solution to the filtrate of 1:1 to obtain a sample-to-be-detected treatment solution; 4, taking 70[mu]L of the ample-to-be-detected treatment solution, adding the ample-to-be-detected treatment solution to a nifedipine detection card in a dropwise manner, observing the change of the color of test paper, preliminarily determining that the sample contains nifedipine if the test paper is yellow or orange red, and comparing the color with a standard color gradation spectrum to realize qualitative analysis; and 5, using a hand-held gold marking color developing instrument to carry out quantitative detection. The detection card developing method includes the following steps: preparing a test paper substrate, preparing a color developing solution, immersing the test paper substrate, preparing detection test paper, and preparing a detection card. The detection method is suitable for onsite rapid detection of the chemical component nifedipine in the blood pressure reducing health foods.