The invention discloses damping glue for a vibration reducing plate and a preparation method thereof. The component formula of the damping glue is as follows: 3 to 10 parts of nitrile-butadiene rubber 26 (NBR 26), 5 to 7 parts of nitrile-butadiene rubber 40 (NBR 40), 2 to 4 parts of additive, 2 to 12 parts of epoxy resin (EP), 1 to 5 parts of phenol formaldehyde resin (PF), 1 to 2 parts of curingagent, 0.3 to 0.5 part of peroxide, 0.5 to 1 part of zinc oxide, and 65 to 75 parts of solvent. The preparation process of the damping glue is as follows: the NBR 26 is firstly plasticated on a double-roll machine for 5 to 10 minutes, and then the zinc oxide is added and mixed with the NBR26 until the Williams plasticity is between 0.2 and 0.3; then the NBR40 is plasticated on the double-roll machine until the Williams plasticity is between 0.3 and 0.4; the mixed material is added to the solvent being stirred and stirred until being completely dissolved; and afterwards, the PF, the additive, the EP or a compound thereof, the curing agent and the peroxide are stirred until being completely dissolved into an evenly thick liquid, and then the normal-temperature damping glue for the vibrationreducing plate can be acquired. The main performances of the manufactured damping glue are as follows: the solid content is 25 to 35 percent; the glue solution viscosity (measured by a rotational viscometer) is 3.5 to 7 Pa.S (25 DEG C); the T-peel strength is larger than 20N/cm; the tensile shear strength is larger than 7MPa; tangent Delta is larger than or equal to 0.20; and the temperature range is minus 10 DEG C to 75 DEG C.