This review discusses recent advancements in second-generation bioethanol production, focusing on pretreatment methods, process conditions, and genetic approaches to enhance ethanol yield. It also summarizes the socio-economic and environmental impacts of bioethanol production. Bioethanol is produced from lignocellulosic biomass (LCB), which is abundant and renewable. LCB consists of cellulose (40–60%), hemicellulose (25–40%), and lignin (15–25%). Pretreatment methods, such as mechanical, chemical, and biological processes, are used to break down LCB and release fermentable sugars. Enzymatic hydrolysis is then used to convert cellulose and hemicellulose into glucose and other sugars. Fermentation processes, such as simultaneous saccharification and fermentation (SSF), are used to convert these sugars into ethanol. The ethanol yield is influenced by factors such as substrate concentration, temperature, pH, and the presence of inhibitors. Genetic engineering approaches are being explored to improve ethanol production by modifying microorganisms to tolerate ethanol and utilize a variety of sugars. The review also highlights the environmental and economic impacts of bioethanol production, including the need for sustainable practices and the potential of algal biomass as an alternative feedstock. The study emphasizes the importance of optimizing pretreatment, hydrolysis, and fermentation processes to achieve higher ethanol yields and reduce production costs.This review discusses recent advancements in second-generation bioethanol production, focusing on pretreatment methods, process conditions, and genetic approaches to enhance ethanol yield. It also summarizes the socio-economic and environmental impacts of bioethanol production. Bioethanol is produced from lignocellulosic biomass (LCB), which is abundant and renewable. LCB consists of cellulose (40–60%), hemicellulose (25–40%), and lignin (15–25%). Pretreatment methods, such as mechanical, chemical, and biological processes, are used to break down LCB and release fermentable sugars. Enzymatic hydrolysis is then used to convert cellulose and hemicellulose into glucose and other sugars. Fermentation processes, such as simultaneous saccharification and fermentation (SSF), are used to convert these sugars into ethanol. The ethanol yield is influenced by factors such as substrate concentration, temperature, pH, and the presence of inhibitors. Genetic engineering approaches are being explored to improve ethanol production by modifying microorganisms to tolerate ethanol and utilize a variety of sugars. The review also highlights the environmental and economic impacts of bioethanol production, including the need for sustainable practices and the potential of algal biomass as an alternative feedstock. The study emphasizes the importance of optimizing pretreatment, hydrolysis, and fermentation processes to achieve higher ethanol yields and reduce production costs.