The invention relates to a method and device for adjusting lifting height of a coil-borne trolley. The method comprises the following steps: acquiring the radius of a coil; acquiring a deviation value of the height of a V-shaped saddle of the trolley based on the radius of the coil and dimensional parameters of the V-shaped saddle of the trolley that bears the coil, wherein the deviation value is particularly a height difference between a datum point of the V-shaped saddle of the trolley and the lowest point of the coil in the V-shaped saddle of the trolley; determining the height to be lifted of the coil based on the deviation value, the radius of the coil and the dimensional parameters of the V-shaped saddle of the trolley; and controlling the trolley that bears the coil to be lifted by the height based on the height to be lifted of the coil to center a spindle of a coiling block of an uncoiler. Further, the accuracy in controlling the lifting height of the coil is improved. The core of the coil cannot be influenced during coiling and uncoiling of the coil. Thus, the production efficiency is effectively improved.