Abstract: For distortion problem of fisheye images collected by video monitoring system of coal mine, an automatic obtaining method of adjustment parameters was put forward based on image content according to line constrain of ideal spherical perspective projection model. The method detects image edge characteristic lines by preprocessing the fisheye distortion image using math morphologic and random Hough transform, then gets the optimal adjustment parameters through the statistic of horizontal and vertical lines proportion. In order to decrease effect of large image information on adjustment parameter obtaining, the ideal spherical perspective projection model was improved and an improved adjustment method of fisheye distortion images was proposed, which realized center transfer of the fisheye distortion image and magnifying of part regions. The experimental results show the method can get a better adjustment effect of fisheye distortion image.