The purpose of bridge maintenance is to maintain the normal traffic function of the bridge, to meet the requirements of load,speed and other factors, and to prevent sudden and serious disasters. Bridge maintenance has the characteristics of long-term, local and emergency. At present, there are special bridge maintenance institutions which have formed systems and specifications for daily inspection, regular inspection, special inspection, special inspection, maintenance and reinforcement of bridges. The maintenance contents and key points have been clearly defined and implemented, and the maintenance technology can meet most of the requirements. At present, the outstanding problem is how to achieve rapid maintenance and emergency treatment. High speed railway and urban rail transit are in uninterrupted operation, high-density traffic, and construction is prohibited during traffic. They can only use the skylight time of 0~4 a.m. every day for maintenance, and the line must be opened after 4 a.m. every day. Highway also requires continuous maintenance. After the occurrence of sudden disasters, it needs emergency treatment and maintenance. The maintenance system of railway system makes it easier to collect data and realize data standardization. Bridge maintenance is developing in the direction of rapid maintenance and intelligent maintenance. This paper mainly introduces the research progress of bridge maintenance in 2020 from three aspects: disease and treatment, maintenance strategy and new maintenance technology.