Lactate dehydrogenase B (LDHB) is widely expressed in adult somatic tissue and is one of the two subunits of lactate dehydrogenase, which is the key glycolytic enzyme and catalyzes the interconversion of pyruvate and lactate. However, the roles of LDHB in glycolysis and tumor progression were obscure in different types of cancer. Here, we determined the roles of LDHB in pancreatic cancer development and progression. We found suppressed expression of LDHB in pancreatic cancer which was due to promoter hypermethylation and deceased expression of LDHB led to glycolytic transition. Functional analysis revealed that suppressed expression of LDHB promoted pancreatic cancer cells proliferation, invasion, and migration in hypoxia. Thus, LDHB might function as a suppressor of glycolysis and suppressed pancreatic cancer progression.