Based on a comprehensive analysis of the subjective operation risk and objective operation risk sources in the five aspects of "people-vehicle-road-management-environment" of highway tunnel, this paper presents a highway tunnel group operation safety assessment method,which mainly based on safety factors and risk factors. The safety factor covers 8 categories, a total of 160 items, including the whole tunnel group, lighting facilities, traffic control, communication, escape and rescue, fire protection, ventilation, and emergency management. The risk factors cover 11 categories such as the whole tunnel group , road structure, traffic volume and traffic pattern. This assessment method integrates operation safety assessment into the design, construction, maintenance and daily management of highway tunnels, and provides powerful technical support for improving the safety of highway tunnel effectively.