As civil infrastructures get larger and more complex, the development of robot technologies that help to construct, monitor, inspect, and manage civil infrastructures is in need. In this paper, we introduce two major robot technologies for construction and monitoring of civil infrastructures. The first one is the beacon-based localization technology for the robust localization of the robot and human. A novel beacon-based localization method is proposed where it utilizes the map information of the structure and the signal propagation model. The second one is the modular robot system for structural health monitoring (SHM) of large structures. To develop an SHM system that directly measures the deformation of the structure using low-cost sensor, a paired structured light (SL)-based modular robot system is proposed. The proposed module which uses one or two actuated lasers and a camera in pair is inexpensive to implement and it can directly measure the accurate relative deformation between any two locations on the structure. To demonstrate the feasibility and capability of the proposed methods, experimental results have been shown for each technology.