The invention discloses a process method for treating a 65Mn steel material through ECAE (Equal Channel Angular Extrusion). The material is subjected to extrusion treatment by adopting a specific process and utilizing a plurality of moulds, so that original pearlite structures in the material are plastically deformed greatly; cementite structures in pearlites are damaged; cementites are uniformly dissolved in an ultrafine grain ferrite substrate structure; finally, an equiaxial ultrafine grain structure is formed. The material structure is improved, the performance is improved, and the material is more applicable to agricultural mechanical tillage and soil preparation machines.