The invention relates to a column plastic pipe pressureproof combined type fuel tank. On the basis of the traditional automobile fuel tank, a column plastic pipe is combined to be a urea reducing agent pressureproof pipe body and a urea reducing agent dosage control box, so that one tank body has three functions, compact design is realized, thus being beneficial to beautiful design of vehicle, mounting of connecting pieces is reduced, vehicle allocation is simplified, and weight is reduced, thereby not only meeting the SCR standard more than China 4 but also reducing system cost.