The invention discloses a production process of a continuous casting gear steel bar for rail transit, and relates to the technical field of steel production. The production process adopts a production mode of continuous casting and continuous rolling to replace a production mode of die casting and forging. The production process comprises the steps of EAF smelting, LF refining, VD refining, wire feeding, fine component adjustment, static stirring, continuous casting, casting blank slow cooling, heating, rolling, pit entering slow cooling, high-temperature tempering, straightening, peeling, ultrasonic flaw detection, finished product inspection, packaging, marking, weighing and warehousing. The production process aims at the purity control problem, the segregation control problem and the hardness control problem in the production process, the preparation method is provided, and the gear steel with the purity, the structure, the hardenability, the grain size and the surface quality meeting the rail transit requirements can be prepared.