The invention discloses an SAR image segmentation method based on feature learning and sketch line constraint, mainly used for solving the problem that SAR image segmentation in the prior art is inaccurate. The SAR image segmentation method comprises the following implementation steps of: (1), sketching an SAR image; (2), according to an area chart of the SAR image, dividing a pixel subspace of the SAR image; (3), performing feature learning by adopting a deconvolution model; (4), constructing a direction feature vector and a length feature vector, and performing filter structure clustering; (5), performing codebook projection based on direction constraint; (6), dividing a hybrid aggregation structured surface feature pixel subspace of the SAR image; (7), performing independent target segmentation based on the sketch line aggregation feature; (8), performing line target segmentation based on a visual semantic rule; (9), performing segmentation of a pixel subspace in a homogeneous area by adopting a polynomial-based logistic regression prior model; and (10), combining to obtain an SAR image segmentation result. By means of the SAR image segmentation method disclosed by the invention, the good segmentation effect of the SAR image is obtained; and the SAR image segmentation method can be used for semantic segmentation of the SAR image.