An industrial vehicle comprising: a machine room including an engine room and a ventilation room which are separated by a dividing wall in a forward/rearward direction; an engine arranged in the engine room; an exhaust gas treatment device arranged in the engine room so as to be located above the engine, the exhaust gas treatment device including a pretreatment unit accommodating a diesel oxidation catalyst and extending in the forward/rearward direction, a selective catalytic reduction unit located adjacent to the pretreatment unit and extending in the forward/rearward direction, a connecting pipe including a mix portion, a first bent portion, and a second bent portion, the mix portion being located between the pretreatment unit and the selective catalytic reduction unit and extending in the forward/rearward direction, the first bent portion connecting the mix portion and an outlet of the pretreatment unit, the outlet being located close to the dividing wall, the second bent portion connecting the mix portion and an inlet of the selective catalytic reduction unit, the inlet being located far from the dividing wall, and a urea water injection device attached to the first bent portion of the connecting pipe so as to be located on an extended line of the mix portion and configured to inject urea water into an exhaust gas; a urea water tank arranged outside the engine room and storing the urea water; and a urea water pipe configured to guide the urea water from the urea water tank to the urea water injection device and penetrating the dividing wall, wherein: a position where the urea water pipe penetrates the dividing wall is located lower than the urea water injection device; and the urea water pipe is inclined obliquely downward from the urea water injection device toward the dividing wall, wherein the position where the urea water pipe penetrates the dividing wall is located lower than a lower end of the connecting pipe, characterized in that the dividing wall includes an upper portion facing the pretreatment unit and the selective catalytic reduction unit, the upper portion being inclined so as to get close to the pretreatment unit and the selective catalytic reduction unit as the upper portion extends downward; and the urea water pipe penetrates the upper portion of the dividing wall. a machine room including an engine room and a ventilation room which are separated by a dividing wall in a forward/rearward direction; an engine arranged in the engine room; an exhaust gas treatment device arranged in the engine room so as to be located above the engine, the exhaust gas treatment device including a pretreatment unit accommodating a diesel oxidation catalyst and extending in the forward/rearward direction, a selective catalytic reduction unit located adjacent to the pretreatment unit and extending in the forward/rearward direction, a connecting pipe including a mix portion, a first bent portion, and a second bent portion, the mix portion being located between the pretreatment unit and the selective catalytic reduction unit and extending in the forward/rearward direction, the first bent portion connecting the mix portion and an outlet of the pretreatment unit, the outlet being located close to the dividing wall, the second bent portion connecting the mix portion and an inlet of the selective catalytic reduction unit, the inlet being located far from the dividing wall, and a urea water injection device attached to the first bent portion of the connecting pipe so as to be located on an extended line of the mix portion and configured to inject urea water into an exhaust gas; a urea water tank arranged outside the engine room and storing the urea water; and a urea water pipe configured to guide the urea water from the urea water tank to the urea water injection device and penetrating the dividing wall, wherein: a position where the urea water pipe penetrates the dividing wall is located lower than the urea water injection device; and the urea water pipe is inclined obliquely downward from the urea water injection device toward the dividing wall, wherein the position where the urea water pipe penetrates the dividing wall is located lower than a lower end of the connecting pipe, characterized in that the dividing wall includes an upper portion facing the pretreatment unit and the selective catalytic reduction unit, the upper portion being inclined so as to get close to the pretreatment unit and the selective catalytic reduction unit as the upper portion extends downward; and the urea water pipe penetrates the upper portion of the dividing wall. a position where the urea water pipe penetrates the dividing wall is located lower than the urea water injection device; and the urea water pipe is inclined obliquely downward from the urea water injection device toward the dividing wall, wherein the position where the urea water pipe penetrates the dividing wall is located lower than a lower end of the connecting pipe, characterized in that the dividing wall includes an upper portion facing the pretreatment unit and the selective catalytic reduction unit, the upper portion being inclined so as to get close to the pretreatment unit and the selective catalytic reduction unit as the upper portion extends downward; and the urea water pipe penetrates the upper portion of the dividing wall.