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Failure of brazed joints is studied using the cohesive zone model (CZM) concept. The CZM provides a constitutive model by defining a relationship between traction and separation at the fracture process zone. The model is characterized by the two parameters of cohesive strength and separation energy. In this study, the CZM parameters of butt-brazed joints are determined in the normal mode of fracture. The tensile strength of the joints is obtained through uniaxial tensile test. To extract the separation energy, a four-point bend test is performed on butt-brazed rectangular beams. The bending test is numerically simulated, and the joint is modeled by employing the cohesive elements available in ABAQUS 6.7 software. The numerical load-displacement curve is fitted to that of the experiment to find the value of the second parameter. The results were verified by the optical measurement of the matching fracture surface heights on the corresponding 3-D profiles.