An exhaust gas purification device including: a tube-shaped casing; a pipe that is disposed at the downstream side of the casing, is inserted into the casing so as to extend in a direction substantially perpendicular to the axial direction of the casing, and is provided with a through-hole communicating with the casing; a guide member that guides the exhaust gas inside the casing to the through-hole; and an injection device that injects a reduction agent from an upstream end of the pipe into the pipe. Then, the guide member includes a turning guide member that guides the exhaust gas to the through-hole from the tangential direction of the pipe so as to generate a swirl flow inside the pipe and a protecting guide member that covers the upstream side of an injection area of the reduction agent in the axial direction of the casing.