The invention provides a traffic safety system. The traffic safety system comprises a hydraulic motor used for driving a vehicle load, a power pump used for outputting constant flow according to a designed flow of the hydraulic motor and a driving assembly used for driving the power pump. The power pump comprises a main pimp and an auxiliary pump. The driving assembly comprises a main pump driving part and an auxiliary pump driving part. The main pump driving part controls the output flow of the main pump according to the vehicle speed. The auxiliary pump driving part controls the supplementary output flow of the auxiliary pump according to the output flow of the main pump. The traffic safety system has the advantages that the safety, stability and reliability of the system are improved.