To provide an engine with an exhaust gas treatment device capable of easily coping with a change of an attaching position of the exhaust gas treatment device to an engine body.

In the engine with the exhaust gas treatment device provided with the exhaust gas treatment device housing a DPF in the engine body, a plurality of exhaust gas temperature sensors are provided in the exhaust gas treatment device, electric wires 12a-14a are connected to the plurality of the exhaust gas temperature sensors, respectively, relay connecters 12b-14b are arranged in the way of the electric wires 12a-14a. When an exhaust gas pressure difference sensor 11 is connected to the exhaust gas treatment device, the relay connecters 12b-14b and the exhaust gas pressure difference sensor 11 are collectively attached to a single bracket 31, and the bracket 31 is attached to the engine body 18.