Bridges serve as important hubs of transportation systems and face increasing structural safety challenges with the growth in service life and traffic loads, as well as environmental impacts. Regular inspection is therefore necessary, and UAV technology is increasingly used to provide a convenient and efficient means for bridge inspection. Three key technologies, which are crucial for UAVs to efficiently address challenges in bridge inspection operations, were analyzed. These include UAV design technology adapting to complex bridge environments, autonomous inspection technology, and intelligent damage-image processing technology. Based on the current research progress and application of these technologies, the technical bottlenecks of applying the present UAV technology in bridge inspection were systematically summarized, and the limitations of existing relevant technologies were discussed in depth as well as their future development trends. Issues related to energy management for low-speed cruise and long-endurance flight, unconventional autonomous positioning and navigation under complex structural space, and intelligent path planning utilizing structural and environmental conditions were examined to broaden new ideas for effective solutions of these problems. Comprehensive analysis indicates that there is a considerable gap between bridge inspection utilizing current UAV technology and fully autonomous operation. However, related technologies demonstrate strong development potential and broad research prospects. UAV-based bridge inspection is expected to evolve toward higher levels of intelligence, automation, and efficiency in the future.