This document summarizes a study on the mechanical properties of concrete made using banana stem ash and straw-dipped water. Banana stem ash was used to replace cement by 5-20% and straw-dipped water was used instead of normal water. Specimens were cast and tested at 7, 14, and 28 days to determine compressive, tensile, and flexural strengths. The results showed that concrete with 5-10% banana stem ash replacement and straw-dipped water had higher strengths compared to normal concrete, while higher replacements of 15-20% had lower strengths. Using agricultural waste materials like banana stem ash and bacteria-enhanced straw water provided an economical and sustainable alternative concrete.