The invention relates to the technical field of steelmaking, in particular to a method for increasing the fast replacement success rate by decreasing the drawing speed through a continuous casting machine. According to the method for increasing the fast replacement success rate by decreasing the drawing speed through the continuous casting machine, the drawing speed is decreased when a tundish isreplaced, the time of passing of a casting blank through a secondary cooling chamber is prolonged, and thus the cooling strength of the casting blank is improved; the temperature of the casting blankis lower before the fast replacement drawing speed returns to zero, in this way, the relative deformation quantity of the casting blank staying in the secondary cooling chamber is smaller in the period that the fast replacement drawing speed returns to zero and casting is started again, it is ensured that when a new tundish starts to be cast, the casting blank can be normally drawn out of a crystallizer under the current pressure of straightening rollers, straightening cracks are avoided, the success rate of fast replacement and casting starting is increased, the quality of the casting blank is guaranteed, and operation is easy; and in addition, when casting is started again, connecting rods are utilized as a connector, after high-temperature molten steel flowing into a copper pipe in thecrystallizer makes contact with the connecting rods, heat of the molten steel is absorbed, the molten steel is solidified while the connecting rods are smelted, thus the connecting effect is achieved,the breed-out situation is avoided, and successful casting starting is guaranteed.