Disclosed is a lateral flow quantitative assay method capable of quantitatively determining the concentration and analyzing the spatial distribution of a disease marker by employing the principle of the laser-induced fluorescence detection technique, which is based on detecting emitted fluorescence when laser light is focused to the disease marker deposited onto a lateral flow quantitative assay chip. The present invention discloses a strip, a laser-induced epifluorescence detection device and a small scanner for the assay method. The present assay method is advantageous in terms of allowing quantitative point-of-care diagnostics in hospitals, being capable of specifically detecting a disease marker by optimizing a lateral flow assay biochip for diagnosis of a specific disease, allowing more accurate quantitative analysis of analytes, and being capable of simultaneously analyzing several cancer markers, reducing the hook effect and expanding the detection range and accurately measuring concentration of analytes.