Disclosed are urea-water solution heating and cooling devices for construction equipment for reducing nitrogen oxides in an exhaust gas discharged from an engine. The urea-water solution heating device, according to the present invention, comprises: an SCR mounted on an exhaust pipe of an engine to perform a reduction process on nitrogen oxides in an exhaust gas discharged along the exhaust pipe; an urea-water solution tank that stores an urea-water solution; an injector mounted on the exhaust pipe on the upstream side of the SCR to inject the urea-water solution supplied from the urea-water solution tank into the exhaust pipe; a valve installed on a conduit between a cooling water pump and the urea-water solution tank to supply engine cooling water introduced from the cooling water pump to the urea-water solution tank when being opened in order to increase the temperature of the urea-water solution in the urea-water solution tank to a set value; and a controller that opens the valve in order to supply the en
