The present disclosure relates to systems and methods for extracting a vessel of a lower limb. The methods may include obtaining an original image including a plurality of image data, in some embodiments, each of the plurality of image data may correspond to a pixel (or a voxel), the plurality of image data may include a target data set, the target data set may represent a first structure extracting a first reference data set from the plurality of image data, in some embodiments, the first reference data set may include the target data set and a second reference data set, the second reference data set may include data of a second structure extracting the second reference data set from the plurality of image data and obtaining the target data set based on the first reference data set and the second reference data set.
