The invention relates to the technology of natural zeolite material modification and aims to provide a nitric oxide adsorbent prepared by supercritically modifying natural zeolite. The adsorbent is prepared by a method comprising the following steps: dissolving a volatile metallo-organic compound into a supercritical medium and placing the natural zeolite undergoing dealuminzation and ammonium exchange in the atmosphere to carry out supercritical replacement in the supercritical atmosphere; drying at the temperature of 120 DEG C after alcohol washing and water washing and then roasting at the temperature of 300-600 DEG C, thus obtaining the metal element containing nitric oxide adsorbent prepared by modifying natural zeolite, wherein the volatile metallo-organic compound is any one of ester, alcoholate or corresponding metal chloride which can be dissolved in the supercritical medium of Ti, Zr, Al, V or Sn. The adsorbent can be used as the environmental function material and is used for adsorbing and purifying the industrial tail gases, flue gases and automobile tail gases containing nitric oxides. The nitric oxide adsorbent has low production cost and has wide market prospect as the environmental function material.