Rotman lens is widely used in multibeam antennas for beam forming networks (BFN) which give required aperture distribution in arrays. Discrete beam-scanning can be fulfilled by switching the beams. However, the size of the feeding circuit using Rotman lens is large. Therefore, beam-scanning microstrip antenna in multi-layer configuration is in the development of this work. Rotman lens was developed at 76.5 GHz for the feeding circuit of the antenna. The simulated and measured performances are presented in this paper.