The defocus and correspondence (DCDC) algorithm uses the spatial information and angular information of four-dimensional light field to complete depth estimation. The defocus response function established by the DCDC algorithm has the problems of limited second-order derivative direction and positive and negative energy offset, which limit its depth reconstruction accuracy in complex scenes. Aiming at the problems, the defocusing response function is improved, and a light field depth estimation algorithm based on energy enhanced defocusing response is proposed. The algorithm fully considers the influences of the surrounding pixels on the defocusing degree of the current position, and realizes the energy enhancement of the defocusing response by increasing the number and direction of second-order derivatives with different weights. Experiments verify the effectiveness of the proposed method. For some light field images with complex boundaries, the depth map obtained by the proposed algorithm has better visual effects. Compared with the DCDC algorithm, the root mean square error of the depth image obtained by the proposed method decreases by 3.95% on average.