The invention discloses a method for controlling straight running of a bulldozer. The method comprises the steps of 1) obtaining the speed difference delta n of left and right motors; 2) determining whether the rotation speed of the left motor is large, performing step 3) if the rotation speed of the left motor is large, and performing step 4) if the rotation speed of the left motor is not large; 3) controlling the control current of a left hydraulic pump to reduce delta i and/or the control current of a right hydraulic pump to increase delta i; 4) controlling the control current of the left hydraulic pump to increase delta i and/or the control current of the right hydraulic pump to reduce delta i. According to the method for controlling straight running of the bulldozer, a small amount approaching principle is used, in each scanning period, the pump displacement of the fast side is reduced by a small amount delta i and/or the pump displacement of the slow side is increased by a same small amount delta i, and balance of speeds of the two sides can be reached within a short time by the aid of the high-speed processing capacity of a controller; besides, overregulation and shock cannot occur as the rectifying amount of each time is small. The invention further discloses engineering machinery using the method for controlling straight running of the bulldozer.