Prestressing tendons are crucial load-bearing elements in post-tensioned prestressed hollow-core slab bridges. Damage to these tendons significantly reduces the safety, functionality, and longevity of the bridge. Regular monitoring of prestressing tendons is essential for bridge operation. Acoustic emission technology, known for its high accuracy and sensitivity to minor vibrations, is a key technique for monitoring bridge cables. This study proposes a novel dual-sensor acoustic emission localization method for detecting tendon damage in post-tensioned prestressed hollow slab bridges, utilizing waveguide rod technology. The effectiveness of this method is confirmed through hammering tests that simulate acoustic emission damage on operational hollow slab bridges. This approach, requiring only two sensors, offers a cost-effective alternative for monitoring the entire span of post-tensioned prestressed hollow-core slab bridges, in contrast to existing acoustic emission localization methods.