Abstract: A caustic parabolic curved antenna for spatial power combination is proposed in this paper.The reflector antenna is formed by aparabola in the xoz plane orthogonal scanning along the other parabola in the yoz plane.And antenna is offset fed with a line array of 8 E-plane sector horns.Both the impact of antenna structural parameters to the antenna performance and the electric scanning properties of the transversal displacement from focus are studied.A formula is given to configure the phases of the array for a given beam deflection angle.Simulation and experiment show that the designed antenna can combine a high gain beam at a given direction.Compared with the parabolic cylindrical antenna with the same aperture, the H-plane 3dB beam width decreases from 6.9°to 5°, and the antenna gain increases by 2.2dB.