The invention discloses an 
ethylene absorbent and a preparation method thereof, belonging to the technical field of fruit, vegetable and flower fresh-keeping. The 
ethylene absorbent is prepared by a carrier substance, a 
metal promoter and a main reactant; the carrier substance is 
active carbon, diatomite or 
zeolite; the 
metal promoter is cupric compound, manganous compound or molybdous compound; the weight of the 
metal promotor is 1-5% of that of the carrier substance; the main reactant is the 
divalent compound of 
palladium; the weight of the main reactant is 0.3-5% of that of the carrier substance. The preparation method comprises the following steps: adding the acidified, filtered and dried carrier substance into the 
aqueous solution of the metal promotor to obtain the mixture of the acidified carrier substance and the metal promotor, adding the 
aqueous solution prepared by the main reactant into the above mixture, filtering and 
drying the mixture of 
aqueous solution and the above mixture to obtain the granular 
ethylene absorbent. The invention is widely applied to fresh-keeping of various 
respiration climacteric fruit, vegetables and flowers, and the ethylene absorbent of the invention is green, safe, 
pollution-free and easy to regenerate; in addition, the 
palladium compound in the ethylene absorbent can be recycled.