PURPOSE: To effectively prevent the transmission of hot air generated from an engine by mounting a baffle plate for shutting off a space part between a side frame and function parts, hangingly at the lower face of the body frame of a tractor body and at a part around the front side of the side frame.

CONSTITUTION: A tractor is provided with an engine and other function parts supported on a pair of body frames 5a, 5b disposed along the longitudinal direction of a body lower part. A side frame 7 is disposed on the side of the body frame 5a, and mufflers 9a, 9b are enclosed in the side frame 7. A baffle plate 21 is hangingly mounted at the lower face of the body frame 5a and at a part around the front side of the side frame 7. This baffle plate 21 is brought into contact with the front wall part 7b of the side frame 7 from the lower part of the body frame 5a, and formed obliquely in such a way as to be opened outward. As a result, heat from the engine is prevented from being transmitted as radiant heat to the side frame 7, and thereby the operating efficiency of a cooling system is prevented from being lowered.