In this work, different lactic acid production processes from lignocellulosic raw material (wheat straw, corn stover) by homofermentative amylolytic lactic acid bacterium Lactobacillus amylovorus DSM 20531T were analyzed and compared by means of process sustainability. The results of the research on "Sustainable production of bioethanol and biochemicals from waste agricultural lignocellulosic raw materials" (HRZZ-9158) were used for the analysis and the process sustainability was determined using SPIonExcell computer program. The specific partial area atot whose value represents smaller or greater environmental impact, as well as economic and environmental sustainability, was used for quantization of process sustainability. The calculated partial specific area for lactic acid production processes from wheat straw hydrolyzate and corn stover hydrolyzate are atot = 7411.04 m2 / 1 kg and 5354.35 m2 / 1 kg of produced lactic acid. As the lower value of a partial specific surface represents a greater sustainability of the process from an economic and ecological perspective, it can be concluded that corn stover is more suitable for acid pretreatment and for the production of lactic acid. The partial specific surface for the simultaneous hydrolysis process of pretreated wheat straw (obtained by alkaline pretreatment) and fermentation to lactic acid is at = 6487.56m2 / 1 kg of produced lactic acid. By comparing the process of production of lactic acid from wheat straw by acidic and alkaline pre-treatment it can be concluded that the alkaline precipitation process has greater sustainability than the acid pre-processing of wheat straw.