The invention discloses a sulfur injection method for a continuous reforming apparatuses. The sulfur injection method comprises: replacing a reaction system loaded with a catalyst by using a hydrogen-containing gas, increasing the temperature to 300-480 DEG C, injecting a sulfide into the pipeline between a reforming mixing feeding heat exchanger and a feeding heating furnace, stopping the sulfur pre-injection when the catalyst in a reforming first reactor contains 100-200 [mu]g/g sulfur or the H2S content in the circulating hydrogen is 2-4*10<-6>L/L, and after feeding in a reforming reaction, continuously injecting sulfur into the feeding pipeline of a continuous reforming apparatus. According to the present invention, with the method, the catalytic caking of the metal can be effectively inhibited, the running risk of the continuous reforming device can be reduced, and the running cycle of the device can be prolonged.