The aim of this study is to verify a detection method of defects in a MEA of a PEFC with non-contact. This method is based on a measurement of a current distribution inside the PEFC, which is estimated from magnetic flux densities around the PEFC by an inverse problem analysis using Tikhonov’s regularization. In order to verify the effectiveness of this method, a pseudo-fuel cell which was able to measure current distributions inside itself was used. By this experiment, the methods for disturbance removal in measuring magnetic flux densities and for determination of regularization parameter in using Tikhonov’s regularization were discussed. Furthermore, this detection method was applied to a 1-cell stack with a defect (10 mm × 10 mm), and consequently detected the defect successfully.