For a panoramic optoelectronic detecting system to compensate three disturbances to track offshore targets by azimuth and pitching axes, based on a five dimensional analytical expression for a image line projected on focal plane, a compensation algorithm for azimuth intercept of panoramic image rotation stabilizing sea-sky line, which takes target point and image rotation centerline as the compensation intercept, is derived. The absolute value of the compensation angle is obtained by extracting the arc tangent function for the ratio of the compensation intercept and system focal length. The coordinators of the target image point and image rotation center point is converted into the coordinator of azimuth rotation. The algebraic difference sign for the abscissa of the two points is taken as the sign criterion of the compensation dosage. The algorithm allows the target image point to approach to the image rotation centerline in the case of the nonlinear large-angle image rotation, and always approach to the original point on the focal plane in combination with the compensation algorithm of the vectorial angle for the pitching mechanism. The simulation of the mathematical model shows that a single compensation can reduce the residual by a factor of 1%. The reasonableness of the compensation algorithm for azimuth intercept was proved by an actual condition test.