Efficient calculation method for permeability of large-size digital core

The invention provides an efficient calculation method for the permeability of a large-size digital core, and relates to the technical field of oil and gas development, and the method specifically comprises the following steps: reconstructing the digital core by using a Markov chain Monte Carlo method MCMC. A size of a representative volume element (REV) is determined using a python program. And obtaining an REV data set I by using a python program. And comparing the error between the to-be-screened data and the standard data, removing the REV with the average coordination number or the average aperture exceeding 2%, and finally obtaining an REV screening data set, namely an REV data set I I. And calling an executable file of digital rock core simulation by using a program IV, executing permeability simulation on all REVs in the REV screening data set, and performing permeability prediction. According to the technical scheme, the problem that in the prior art, a large-size digital core permeability prediction