The invention discloses a morphology-based water-land-air boundary line detection method and system, a medium and equipment. The system comprises an image preprocessing module, a morphological gradient processing module, a segmentation processing module and a water-land-air boundary line extraction module. The method comprises the specific steps: preprocessing an obtained original picture, whereinpreprocessing comprises scaling, Gaussian blur denoising and color space conversion processing; obtaining a preprocessed image, wherein the color space conversion processing includes converting an RGB color space into an HSV color space; performing morphological gradient processing on the brightness channel in the HSV color space of the preprocessed image to obtain a morphological gradient map; performing watershed segmentation processing on the morphological gradient image to obtain a segmented image; and extracting land-air lines and land-water lines from the segmented image by adopting anedge detection algorithm. According to the method, the water, land and air boundary line can be rapidly and accurately detected, an important reference standard is provided for autonomous navigation of the unmanned ship, and the unmanned ship can adapt to various water area environments.