The invention discloses a method for toughening and enhancing polyamide, comprising the following steps of: (1) obtaining a polyamide sheet material by machining a polyamide material in high polymer molding and machining equipment, wherein the polyamide material comprises a polymer with a main chain which is wholly or partially formed by carboxyl and amido through condensation polymerization; (2) machining the polyamide sheet material into a needed shape and raising the temperature of the sheet material to a machining temperature to carry out single-faced rolling and plate pressing, wherein the machining temperature is lower than a smelting point of the high polymer, the pressure of the polyamide sheet material is 1-15000 MPa, and the time for being subjected to single time of constant pressure is 10-9000 s; and (3), carrying out heat treatment on the polyamide sheet material, wherein the temperature of the heat treatment is lower than the smelting point and the time is less than 900 min. In the single-faced rolling and plate pressing process, random molecular chains in a previous polymer sheet material are arrayed under the effect of an external force to form an ordered orientation structure, so that the mechanical property of the material is improved.