This research highlights the novelty of using Monte Carlo Simulation Method (MCSM) for material prediction in 3D printing. In the recent years, the production processes pay particular attention to optimize the use of materials. optimizing the product for a certain percentage positively affects the saving of resources, and this fact motivates the development of industries concerning the use of materials. The promising potential of solving this problem has great influence in Additive Manufacturing (AM), especially in 3D printing. In recent years, this technology has received a tremendous developmental jump by introducing the idea of using several materials simultaneously in one production process. Furthermore, a new concept of 3D printers is being introduced to implement this idea both in Fused Deposition Modeling (FDM) and Selective Laser Sintering (SLS) printing. There are still many factors to be considered, and one of them is the mechanical properties of potential multi-material products, especially the determination of these properties and the automation of this process. Therefore, this paper proposes one of the possible methods to solve this problem by introducing Rule of Mixture based on MCSM.