Imaging of 3D structural interfaces through reflected rays shooting from common-shot gathers is presented in this paper. First, by fitting the reflected arrivals picked from common-shot gathers, we calculate apparent dips and the shortest distances between sources and reflectors along two profiles. Then, based on the geometry of the profiles and a planar reflector, a unit normal vector of the reflector is determined from the apparent dips and the azimuths of two oblique profiles. A special case, when apparent dips are zero along two parallel profiles, for determining the reflector normal is also investigated. We propose three criteria to ensure the selected travel-times along two profiles resulting from the same planar reflector. These are that firstly, the same shortest distance from sources to the reflector is utilized; and secondly, we want to ensure the same normal of the reflector, and finally, the same ray distance.