The invention relates to a cardiac marker combined detection device and a preparation method thereof and belongs to the field of medical detection equipment. The cardiac marker combined detection device is prepared from a nitrocellulose membrane with immobilized high-specificity MPO, cTnI, NT-proBNP antibodies and goat anti-mouse IgG polyclonal antibodies, glass fibers adsorbing colloidal gold-labeled MPO, cTnI and NT-proBNP antibodies, a sample pad and an absorbent paper through binding. The preparation method comprises that the nitrocellulose membrane is pretreated through a polylysine treatment solution, MPO, cTnI and NT-proBNP antibodies and silica nanometer particles are bonded and then are adsorbed by the nitrocellulose membrane and an appropriate metal spraying buffer solution and a sample pad treatment solution are prepared. The cardiac marker combined detection device guarantees complete release of immunity colloid gold, effectively improves response sensitivity, reduces a use amount of immunity colloid gold at the same threshold, saves a cost and realizes simultaneous detection of three cardiac markers such as MPO, cTnI and NT-proBNP without increasing of production process complexity. The detection paper has the advantages of high sensitivity, good specificity, operation simpleness, time saving and good practicality.