Acoustic emission (AE) techniques are among the most effective nondestructive evaluation (NDE) methods for the structural health monitoring (SHM) of large-scale infrastructure. These techniques enable the real-time monitoring of concrete cracks and damage to embedded steel reinforcements without causing structural failure. In particular, they are well suited for detecting fractures in tendons within prestressed concrete (PSC) bridges. PSC bridges are structurally classified into internal and external tendon systems, depending on their prestressing method. Although external tendons can be inspected through visual or acoustic methods, detecting defects in internal tendons is significantly more challenging owing to their embedded placement within the concrete. This study highlights the application of AE sensor technology as a core sensing method to capture and interpret material-specific fracture signals from both concrete and steel tendons. The distinction between the acoustic characteristics of concrete cracking and tendon breakage requires tailored signal processing techniques that reflect the physical properties of these structural materials. This study aims to develop an AE-based technology for detecting fracture signals in the internal tendons of PSC bridges and to establish maintenance guidelines for safety inspections and field applications. To achieve this, various simulated fracture tests are conducted to build a database of AE signals associated with tendon fractures. Additionally, field experiments are performed on an in-service PSC bridge in Seoul, South Korea, to evaluate the feasibility of real-world implementation. From the results of these field validation tests, maintenance guidelines for the AE-based monitoring of internal tendon fractures in PSC bridges are proposed.