Concrete is in high demand due to the quick-growing construction industries. The demand for concrete leads to an increase in the use of binding material (cement). The need for a huge quantity of cement leads to the depletion of natural sources, which in turn affects the environment. The purpose of this study was to examine the effects of partially replacing cement with a blend of Marble Dust Powder-Enriched Metakaolin in concrete, to reduce the environmental harm caused by cement production and marble dust. The experimental study involved different partial replacements of the control mix,10%,15%,20%,25%,30, % 35%, and 40%. The cement paste was tested for soundness, setting time, consistency, and workability(slump) as fresh properties, hardened properties (compressive strength, density, and ultrasonic pulse velocity) of the 7th, 28th, 56th, and 90th days, durability properties (water absorption for the 28th, 56th, and 90th days, sulfate resistance for 90th day) and microstructural properties Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), differential thermal analysis (DTA) for 28 days. C-25 concrete based on ASTM standard a total of 192 specimens were used. Based on experimental results, the normal consistency and soundness of the cement paste increase as the percentage of the blend of Marble Dust Powder-Enriched Metakaolin increases. The initial and final setting times of cement paste decrease as the percentage of replacement of cement with Marble Dust Powder-Enriched Metakaolin increases. The use of MDP-EMK has a reduction in the workability of concrete in comparison to the control mix. In the 20% replacement of MDPEMK, the concrete's compressive strength, the concrete's UPV, and bulk density have been improved, particularly in another type of replacement. Furthermore, the incorporation of MDP-EMK enhances the concrete’s durability. The microstructure properties of concrete improved the replacement of the MDP-EMK mix than the control. The use of 30% MDPEMK replaced by cement in the production of concrete has produced low-cost concrete up to 1505.4ETB/m³ (17.07 %) compared to the control mix. KEY-WORDS: Concrete, Compressive strength, Slump, UPV, density, absorption, Metakaolin, Marble Dust Powder.