The invention relates to a crankshaft steel smelting method. According to the method, the contents of elements like Al, O, V, N and S in steel are strictly controlled, oxide with the main component being Al2O3-MnO is obtained in the steel, a large amount of fine MnS can be controlled to be evenly distributed in the steel through the component oxide, and a nucleation core is provided for generating the intragranular ferrites in the cooling process after forging. The number of the MnS obtained through the smelting method is 500/mm<2>, the proportion of the obtained intragranular ferrites is 30% or above, and grain boundary ferrites achieve interrupted distribution.