3D printing is one of the most popular additive manufacturing technique due to its usage in vast applications. The process of 3D printed polycarbonate (PC) reinforced acrylonitrile-butadiene-styrene (ABS) composite increases the mechanical properties and yields higher strength for 3D printed structures/products. In this paper, a comparative study was conducted on PC/ABS polymer composites developed using fused deposition modeling (FDM) and conventional compression molding (CM). The proposed study aims at analyzing 3D printed PC/ABS in terms of their processibility, microstructure, and mechanical performance. Three different specimens were prepared with weight percentages (10 wt%, 20 wt%, and 30 wt%) of PC reinforcement in ABS. Mechanical properties of the specimens are used to find the best composition of the composite using FDM and CM. Similarly, the microstructure of specimens is studied to identify the variations in the strength of the polymer composites. This study proves the compatibility of the two polymers. With an increase in the PC content in the sample, the hardness and strength are improved and can provide an excellent amount of strength to the product at a required concentration of PC reinforcement. This phenomenon was explained based on changes in the void formation using micro-structural study. Knowing the appropriate polymer composition, it contributes to printing complex 3D printed with better rational, aesthetic and economic benefits for different applications such as automotive, marine, and several other fields. © 2019, KSME & Springer.