The invention discloses a rapid image-recognizing method of a power line profile. The method comprises the following steps: (1) conversing a shot color image into a grey image by brightness calculation and extracting the border profile of the image; (2) adopting an improved probability Hough transformation method to make self-adaptive adjustment of a line segment length and a statistics number obtained from the image in a known region; (3) adopting fitting of a line and a direction template for the two-dimensional fitting of a direction pixel template and a distance pixel template with linear characteristics and realizing linear fitting by deriving sumi rho(ri); and (4) calibrating and outputting power line pixels by storing and displaying the finally detected and calibrated linear pixels in a polar coordinate mode or a rectangular coordinate mode. Aiming at the concrete requirements of helicopters or robots for inspecting transmission lines, the invention precisely extracts the transmission lines in real time, provides a solid foundation for the subsequent zoom-in shooting of a camera and the defect detection of parts hereafter and has favorable theoretical and application prospects.