<p>Hinge damage is a common type of damage in prefabricated beam bridges. It is difficult to diagnose hinge damage using the quasi-static displacement influence lines obtained via rapid bridge inspection. To address this issue, a method is proposed to diagnose the hinge damage of prefabricated beam bridges by using the difference between quasi-static displacement influence lines. First, a damage diagnosis feature matrix was established such that the correlation between the quasi-static displacement influence lines of two adjacent beams at different cross-sections of one healthy bridge is close to linear. Second, the damage diagnostic factor was generated by calculating the null space of the abovementioned matrix, and then the probability statistics-based threshold for damage diagnosis was obtained. The numerical examples show that the difference between quasi-static displacement influence lines is more effective for hinge damage diagnosis than the lines themselves. Finally, the effectiveness of the proposed method was empirically validated through experiments on a scaled-down beam bridge model.</p>