The invention discloses a low-noise rack loading mechanism which comprises an oil cylinder and a tooth bar capable of axially moving, the tooth bar axially penetrates through the oil cylinder, and a tooth bar tightness adjusting mechanism is arranged at one end of the tooth bar, the other end of the tooth bar is provided with a limiting mechanism, an oil cavity is formed between the outer wall ofthe tooth bar and the inner wall of the oil cylinder, and oil seals are arranged at the two ends of the oil cavity, the oil seal is arranged between the outer wall of the tooth bar and the inner wallof the oil cylinder, and the outer wall of one end of the tooth bar extending out of the oil cylinder is meshed with the gear shaft. The mechanism has the advantages that loads with different values can be provided as the other mechanisms, little noise can be generated in the using process, and the requirements of the automobile steering gear when carrying out the rack noise experiment are fully met; and the bidirectional damping effect of the tooth bar in the oil cylinder is achieved, and the load is stable.