Abstract: In this study, waste bagasse ash was used as a source material for making geopolymer in order to reduce the negative environmental impact of waste disposal. Ground Bagasse Ash (BA), sodium silicate and NaOH were the materials used. A constant liquid to ash ratio and similar flow were applied to the test. The effects of curing temperature, sodium silicate to NaOH ratio and concentrations of NaOH on strength and porosity were investigated. Test results indicated that the strength of geopolymer mortar was strongly dependent on curing temperature, sodium silicate to NaOH ratio and concentration of NaOH. To obtain good strength and low porosity BA geopolymer mortars, NaOH concentration of 10 M, sodium silicate to NaOH ratio of 2.5 and temperature curing at 65°C should be used. The reasonable strengths of 11.6-15.8 MPa and porosity of 20.5-23.5% were obtained.