It is widely accepted that cement and concrete are substantial sources of CO2 emissions. Researchers have been looking to replace cement with industrial waste to reduce the environmental impact of concrete production. The current research focuses on successfully using marble powder (M) and porcelain powder (P) instead of cement to produce cement mortar. Both mechanical and microstructural characteristics of several single and binary mixtures consisting of M and P were examined, with 13 mixes with M and P having been replaced by 2.5, 5, 7.5, and 10% of cement weight. For all mixtures in this work, compressive strength, flexural strength, SEM analysis, and thermogravimetric analysis (TG/DTA) were applied. The mixtures containing 10% M, 10% P, and 5% M+5% P demonstrated the best results. The maximum values recorded in compressive strength were 52, 55, and 50 MPa, whereas the control mix had 30 MPa. The maximum values for flexural strength were 9.24, 10.64, and 8.4 MPa in comparison with the 7 MPa of the control mix. Moreover, SEM analysis demonstrated the existence of a thick and compacted microstructure, which is predominantly the result of the formation of both Calcium Hydroxide (C-H) and high-density Calcium Silicate Hydrate (C-S-H) phases in all blends. SEM images demonstrated how hydration compounds formed and how the presence of M and P improved bonding. The difference in the quantities and types of phases distinguished by the different types of substitute material was also noted. The decrease in C-H, which is most prominent after a hydration period of 28 days, is primarily attributed to the interaction between C-H and M and P. Thus, this study demonstrates that M and P, by themselves or in combination, can be utilized as alternative resources in the production of high-performance and sustainable concretes.