In this study, a damage identification technique based on the distributed Macro-Strain (MS) response measurements is presented. The fundamental concept of the proposed technique is that the ratio of the strain measured at a target location and a reference location of a beam-like structure is constant for a given condition of the structure. The proposed damage identification technique was verified using the laboratory experimental results. In addition, noise was added to the measured response to simulate the real field condition. The proposed technique was able to identify damage in a noise-polluted environment. The proposed technique was also applied for the health monitoring of a highway bridge in Japan. Long-gage distributed sensors were deployed to collect the traffic induced strain responses. Results from the onsite experiment show the potentials of the proposed technique for practical application.