In this paper, we design and optimize 1X2, 1X4, 1X8, 1X16, and 1X32 optical power splitter based on Multimode Interference (MMI). A mathematical model is used to get accurate values of propagation constants and subsequently calculates the optimum value of coupler length of. This paper aims to study the design, simulation, and optimization of low-loss Y-branch passive optical splitters up to 64 output ports for telecommunication applications. For a waveguide channel profile, the standard material silica-on-silicon is used. The Y-splitters are designed and simulated at. optical transmission systems, using two different design tools employing Beam Propaga-tion Method.