High rate of increase in the prices of cement is worrisome and become burden to people in the entire construction industry. Researchers, civil engineers, builders, architects and all concerns parties in the building industry are desperate for any suitable and effective but cheaper materials that can replace cement. There is need to find an alternative binding material that can be used mainly or in partial replacement of cement. The materials used were sourced from Bida town, Niger state, Nigeria. Wood ash and cassava peel ash were obtained after burning in the furnace at National Cereal Research Institute Badeggi, Bida into ash and passed through 75 micro meter sieve to the finest texture. The water use for the work was free from impurities. The comparative study on the compressive strength of concrete when OPC was partially replaced independently by some percentage of cassava peel ash (C.P.A) and wood ash (W.A) using 0%, 5%, 10%, 15%, 20% and 25% on both materials, 0.5 water-cement ratio and mixed design ration of 1:2:4. The mean strength of concrete at control is 0% (27.11N/mm2), 5% (24.44N/mm2), 10% (23.25N/mm2), 15% (23.36N/mm2), 20% (18.52N/mm2) and 25% (15.93N/mm2). 25% replacement of cement has the lowest mean strength at 28 days. Replacement at 5, 10 15% are within specification of (20N/mm2) for plain concrete while 20 and 25% are not suitable for structural concrete. The higher the pozzolanic material added to the cement in concrete production the lower the strength. The effects of Cassava Peel Ash and Wood Ash as environment pollution can be reduced when utilized as part of cement in concrete production.