Abstract: The speed guidance control of urban expressways can improve the efficiency of road operation and reduce the incidence of accidents. Under the hybrid automatic driving environment, the control effect of speed guidance will be affected by the proportion of automatic driving vehicles. Based on the micro simulation model of Shanghai Expressway, the relationship between the hybrid proportion of automatic driving vehicles and the control effect of speed guidance was studied. The vehicle conflict and the change of travel time under different combinations were analyzed. The results showed that the proportion of autonomous vehicles exerted a certain impact on the speed guidance control effect.