The invention relates to a novel milling mechanism of a surface milling machine. The novel milling mechanism comprises a cylinder barrel; a stepped hole is formed at the middle part of the cylinder barrel in the axial direction; a cylinder rod is inserted into the stepped hole; a connecting flange is fixed to the upper end of the cylinder rod; the upper end of the cylinder barrel is connected andfixed through a fixing flange; the lower end of the cylinder rod penetrates through the cylinder barrel to be provided with a bearing at the end; and the parts, in the stepped hole, of the cylinder rod are sleeved with disc springs. The novel milling mechanism of the surface milling machine is long in service life and low in investment cost; the surface of a surface milling pipe is flat and smoothand surface oxide residues caused by the instability of a servo system is reduced, so that the yield of the subsequent process is raised; the overall environmental protection effect is improved; andthe adaptability to additional loads is high, a casting blank can always be kept in a proper range, the service life of a milling power mechanism is prolonged and the productivity of equipment is improved.