In light of deveolpments in civil engineering, there is an urgent need for innovation in construction supplies, stemming from new formulations that answer economic and enviromental factors. Therefore, the study of the use of natural particles applied to concrete as a pozzolanic material is an option that meets the sustainability requirements and reduces the final cost of concrete. Since the ashes from the banana leaf behaves as posolinic substance, and considering its wide availability in great quantities in Brazil, it would be interesting to analise its aplication on concrete. This study has as its objective to analize the mechanical behavior of Portland cement concretes with partial substitution of the cement with ashas from the banana plant. For this research, concrete was mixed in the proportions of 1:1,89:2,45:0,5 (Cement: Sand: Gravel: water/cement), as was also concrete with the same proportions, only with the 5% and 10% substition of the cement with ashes from the banana plant. Next, the following tests were made on all of the concrete produced: Slump Test, compression resistence, and water absorption. The results demonstrate that as in direct proportion to the increase in the content substitution, the mechanical properties became more efficient, when compared to the reference concrete (with 0% substitution), in all of the analyzed time frames. With reference to the resistence to compression, the optimum substitution was that of 10% in which the resistence increased 65,88% over the reference concrete at 28 days. Besides this, the effect of the pozzolanic matter also reduced the water absorbtion by 22,98%, producing a concrete that is even more resistent to pathological problems. In light of this, the use of banana plant ash as a pozzolanic matter, applied to the concrete in substition to the cement proved itself satisfactory and viable, as verified by the significant results obtained by this study.