A new phase analysis method using mean intensity values on electronic speckle pattern interferometry is proposed for measuring dynamic phenomena with variations of the mean intensity and the modulation amplitude values. In this method, phase differences are calculated by least-squares in kernels using interfered intensity values and mean intensity values of laser speckle pattern images on series deformation states. The interfered images and the mean intensity images are captured simultaneously for each state. For the phase difference calculation, initial phase values are required only for first step. The initial phases are obtained by another phase analysis method. The effectiveness of the proposed method is evaluated using simulation images. As a result, it is verified that the high accuracy phase analysis is possible under the situation with variations of the mean intensity and the modulation amplitude values. Additionally, an interferometer that two images, the interfered speckle image and the mean intensity image, are captured on a single image on a single camera is constructed for measuring displacement distribution. Experiments are then performed for validating availability of the proposed method.