The depletion and environmental problems associated with fossil fuels as main energy sourcernmotivates to look for alternative energy sources that do not compromise both food security andrnthe environment. Sorghum is a fast-growing crop that can be harvested twice a year and producernboth food (grain) and straw that can be utilized for ethanol production. The study explores thernproduction of bioethanol from sequential acidic-alkaline pretreated sorghum straw hydrolysate. rnSequential acid-alkaline pretreatment method was employed to obtain most intactrnmonosaccharides from cellulose and hemicellulose. Dilute sulfuric acid (1%) pretreatment at 125rnâ„ƒ for 10 minutes was used at the first stage mainly for hemicellulose removal. In the second stagernpretreatment, dilute sodium hydroxide (1.25 %) at 90 â„ƒ for 10 minutes was employed forrndelignification. The residues after the second pretreatment were hydrolyzed using dilute sulfuricrnacid of concentrations (2 %, 3%, and 4%), at temperatures (110 â„ƒ, 125 â„ƒ, and 140 â„ƒ) and timesrn(20, 40, and 30 minutes). The sugar concentration of the hydrolysates was determined using phenolrnsulfuric acid method. Three hydrolysates having sugar levels 30.42 g/L, 31.79 g/L, and 32.9875rng/L were selected for fermentation. Response surface methodology, Box-Behnken experimentalrndesign with design expert version 11.1.0.1 was applied to randomize and analyze the effects of thernvariables encountered in fermentation experiments. The experiments were done using the selectedrnhydrolysates, varying size of inoculum (5 %, 10 %, and 15 %), and pH (4.5, 5, and 5.5) at 30 â„ƒrnfor 72 hours. The fermented samples were finally centrifuged and evaporated for purifying thernethanol. The yield of ethanol was determined after determining the percentage ethanol usingrndigital density meter. FTIR analysis was done to determine the functional group of the productrnobtained and the result showed O-H, C-O, and C-H peaks similar to the standard ethanol. Thernresults of the statistical analysis showed that all the three independent factors and the interactionrnbetween sugar level and pH affected the ethanol yield and a maximum of 0.617 mL/g yield wasrnobtained at sugar level of 3.29875 g, pH of 5, and 15 % inoculum size. Generally, controllingrnfermentation parameters during the production of ethanol from sequential acidic-alkalinernpretreated sorghum straw is a good choice in view of increasing yields of sugar and ethanol,rndecreasing dose and cost of chemicals, and minimizing waste generation.