The invention belongs to the field of light field image processing and depth estimation, and particularly discloses an improved light field depth estimation algorithm based on energy-enhanced defocusing response. In order to solve the problem that in the existing DCDC algorithm, when a defocusing response function is established, an adopted Laplace operator has the problems that the second-order derivative solving direction is limited, and all second-order derivative summation energy counteracts each other, a defocusing response function is improved, and an optical field depth estimation algorithm based on energy enhancement defocusing response is provided; according to the algorithm, the influence of peripheral pixel points on the defocusing power of the current position is fully considered; energy enhancement is realized by increasing the number and direction of second-order derivatives with weight difference; experiments verify the effectiveness of the method, for some light field images with complex depth information, the visual effect of the depth image obtained by the algorithm is better, and compared with a defocusing evaluation and correlation evaluation combined algorithm,the mean square error of the depth image obtained by the improved algorithm is averagely reduced by 3.95%.