Four major aspects, i.e., traffic safety, function and service, disaster prevention and control and traffic control should be considered in the design of the traffic engineering facilities of highway tunnels, which consist of traffic signs and traffic mark lines, traffic monitoring facilities, ventilation and lighting facilities, trumpet call system, fire alarming system, fire fighting and escaping facilities, power supply and distribution facilities, central control and management system. In the paper, the guiding principles for the design of the traffic engineering facilities of highway tunnels are presented, the functions of each kind of traffic engineering facilities are interpreted and the problems in the design of the traffic engineering facilities of highway tunnels are pointed out.