Abstract: The disclosure belongs to the technical field of radiomics, and particularly relates to an extraction method for radiomics feature information of knee joint effusion. each layer of an image is segmented into a plurality of regions, the interference of image noises in each region is removed, then whether each region after interference removal is an effusion region or not is judged, finally, the radiomics features of each effusion region are calculated, interpolation processing is respectively implemented on the obtained image position and the area of the effusion regions, an effusion area simulation change curve is drawn, curve integration is implemented to obtain volume information, and all the extracted information is stored in a cell array of a MATLAB. thus the effusion information in the MRI image of the knee joint is automatically extracted, and meanwhile, the method is fast in speed, high in accuracy, good in repeatability.