The invention discloses an aluminum alloy plate for a motorcycle hub and a preparation method of the aluminum alloy plate. The aluminum alloy plate comprises the following elements: Si, Fe, Cu, Mn, Mg, Cr, Zn, Ti and Al. Pure aluminum ingots with purity greater than 99.7%, silica powder, iron powder, copper powder, chromium powder, pure magnesium ingots and aluminum titanium boron wires are subjected to smelting, casting, milling, soaking treatment, hot rolling and annealing to obtain the aluminum alloy plate for the motorcycle hub. According to the method, processes of large slab ingot casting, thick plate hot pressing and annealing are carried out obtain an aluminum alloy thick plate, the aluminum alloy thick plate is subjected to spinning to obtain the motorcycle hub product, the obtained aluminum alloy thick plate is small in internal stress and uniform in chemical ingredients, segregation is eliminated effectively, crystalline grains are broken completely, crystalline grain sizes are uniform, stopping performance is good, wear resistance is high, cavities and slag inclusion are avoided, the service life of the aluminum alloy thick plate for the motorcycle hub can be greatly prolonged, and requirements of the motorcycle aluminum alloy industry are met.