The invention discloses an additive for hot galvanizing, a hot galvanized plating agent, a hot galvanizing method and a hot galvanizing material. The additive comprises the following components in part by weight: 0.25-0.35 part of Ce2O3, 3-5 parts of Al, 2-2.8 parts of Mg, 0.1-0.5 part of Si, 1-3 parts of Sn, 0.1-0.4 part of Bi, and 0.2-1 part of Mn. The additive for hot galvanizing is added in a zinc solution according to the formula ratio to prepare the plating agent. A hot galvanized coating, containing a rare earth oxide of Ce2O3 and metal elements of Al, Mg, Si, Sn, Bi and Mn, can be prepared from the plating agent, so that the corrosion resistance of the hot galvanized coating is 10 times or more of that of a hot galvanized coating adopted in a common hot galvanizing technology, and the maximum corrosion resistance is 12.25 times of the corrosion resistance of hot galvanized coating adopted in a common hot galvanizing technology.