Ethiopia's construction industry is expanding aggressively than ever before. Cement is the most essential and expensive material in this regard. Cement takes 10% -15% by volume of concrete. Now a day the construction industry challenged by the scarcity of cement and price scalation of cement market. However, scholars’ tray to replace cement by natural pozzolan material. Beside of this, investigated that Bamboo leaf ash possesses pozzolanic properties. Ethiopia has about low land Bamboo it covers 850,000 hectares, so it is good to utilize bamboo leaf ash as cement replacement material. In this study, the capability of Lowland Ethiopian Bamboo Leaf Ash as a partial substitute for cement in C-25 concrete production with 0%, 5%, 10%, 15%, and 20% replacement of OPC by BLA with 0.49 percent water to cement ratio is investigated. The study examine; chemical properties of BLA, Physical properties of cement paste, workability, compressive strength, water absorption, density, sulfate attack and microstructure by FTIR and TGA of concrete was investigated. The chemical composition of Bamboo leaf ash was examined and the summation of SiO2, AlO3, and FeO3 is 76.35% and the ash was classified class N pozzolan. The normal consistency percent of water increase as the BLA replacement amount increase and both initial and final setting time rang increase as the BLA replacement amount increase. The compressive strength of concrete for 5% and 10% BLA achieves the target mean strength (33.5Mpa) on the 28 day, and on the 56 day, 5% and 10% replacement increase the concrete strength by 1.84% and 0.12%, respectively. The water absorption and sulfate attack have significant improvement of the BLA blended concrete on 5% and 10% BLA content. TGA examination verified that the 5% and 10% BLA replacements were more thermostable than the control mix, and FTIR analysis demonstrated the concentration of Ca(OH)2 decreases throughout the combination. Bamboo leaf ash has good pozzolanic characteristics, according to the result. The outcome of the study will balance the cement price escalation and increase housing affordability without compromising quality.