The development of intelligent connected vehicles has placed higher demands on automotive braking systems, and traditional braking systems are gradually being replaced by brake-by-wire systems. With their outstanding response speed and control precision, brake-by-wire systems have become the core execution foundation for achieving high-level autonomous driving and even unmanned driving. This paper systematically reviews and summarizes the development history, architecture, classification, key technologies, and applications of the brake-by-wire systems for intelligent connected vehicles; analyzes the structural schemes and advantages and disadvantages of different types of brake-by-wire systems, and combs and analyzes key technologies such as master cylinder hydraulic pressure control, wheel cylinder hydraulic pressure control, wheel cylinder hydraulic pressure estimation, solenoid valve control, and clamping force control. It also outlines two active safety control technologies based on brake-by-wire systems: ABS and AEB, as well as brake energy recovery technology. It analyzes and summarizes the current challenges faced by intelligent connected vehicle brake-by-wire technology and its future development trends. The brake-by-wire technology for intelligent connected vehicles is evolving from EHB to EMB, but it still faces many challenges such as insufficient motor power and compatibility issues of electronic components. There is an urgent need to improve the system’s integration and redundancy to meet the reliability and safety requirements of high-level autonomous driving.