An exhaust purification system comprising: an exhaust pipe (11, 12, 13, 14), which has a straight line shape, and through which exhaust gas discharged from an engine flows; an injection nozzle configured to inject a reducing agent into the exhaust pipe in a direction obliquely with respect to an axial direction of the exhaust pipe; a reduction catalyst provided in an exhaust system that is on a downstream side of the injection nozzle and configured to purify the exhaust gas by reacting the exhaust gas with the reducing agent; and a mixer member provided inside the exhaust pipe on the downstream side of the injection nozzle and on an upstream side of the reduction catalyst and configured to mix and diffuse the reducing agent with the exhaust gas, wherein the mixer member comprises a plurality of fins (54A, 54B) protruding to the downstream side, and wherein the mixer member is arranged inside the exhaust pipe in an inclined manner such that an upstream side surface of the mixer member, which is on an opposite side of the fins (54A, 54B), faces an injection port surface of the injection nozzle; and characterized in that the linear piping is formed in a cylindrical shape, and wherein the mixer member comprises: an elliptic annular shaped ring member, an outer periphery of the ring member being fixed to an inner periphery of the linear piping; a plurality of plate members (53A, 53B) arranged inside the ring member in a grid shape; and the plurality of the fins (54A, 54B) that is integrally formed with the plurality of plate members (53A, 53B) and is bent at a predetermined angle. an exhaust pipe (11, 12, 13, 14), which has a straight line shape, and through which exhaust gas discharged from an engine flows; an injection nozzle configured to inject a reducing agent into the exhaust pipe in a direction obliquely with respect to an axial direction of the exhaust pipe; a reduction catalyst provided in an exhaust system that is on a downstream side of the injection nozzle and configured to purify the exhaust gas by reacting the exhaust gas with the reducing agent; and a mixer member provided inside the exhaust pipe on the downstream side of the injection nozzle and on an upstream side of the reduction catalyst and configured to mix and diffuse the reducing agent with the exhaust gas, wherein the mixer member comprises a plurality of fins (54A, 54B) protruding to the downstream side, and wherein the mixer member is arranged inside the exhaust pipe in an inclined manner such that an upstream side surface of the mixer member, which is on an opposite side of the fins (54A, 54B), faces an injection port surface of the injection nozzle; and characterized in that the linear piping is formed in a cylindrical shape, and wherein the mixer member comprises: an elliptic annular shaped ring member, an outer periphery of the ring member being fixed to an inner periphery of the linear piping; a plurality of plate members (53A, 53B) arranged inside the ring member in a grid shape; and the plurality of the fins (54A, 54B) that is integrally formed with the plurality of plate members (53A, 53B) and is bent at a predetermined angle. an elliptic annular shaped ring member, an outer periphery of the ring member being fixed to an inner periphery of the linear piping; a plurality of plate members (53A, 53B) arranged inside the ring member in a grid shape; and the plurality of the fins (54A, 54B) that is integrally formed with the plurality of plate members (53A, 53B) and is bent at a predetermined angle.