Gastric cancer is a common malignancy in the alimentary system. The laminin subunit gamma 1 (LAMC1) is an important oncogene in human cancers. However, how and whether LAMC1 takes part in gastric cancer progression is largely uncertain. This study analyzed the association between clinical factors of patients and LAMC1 expression and explored the influence of LAMC1 silencing on cell proliferation, migration, invasion, the Warburg effect, protein kinase B (AKT) pathway, and mitogen-activated protein kinase (MEK)/extracellular regulated protein kinase (ERK) pathway in gastric cancer cells. Our results showed LAMC1 abundance was enhanced in gastric cancer samples and cells. LAMC1 was related to the clinical stage, tumor depth, lymph node metastasis, and distant metastasis of patients. LAMC1 silencing inhibited cell proliferation, migration, and invasion. Moreover, LAMC1 knockdown suppressed the Warburg effect via decreasing lactate production, lactate dehydrogenase (LDH) activity, and glucose uptake. LAMC1 interference blocked the activation of the AKT and MEK/ERK signaling. Collectively, LAMC1 knockdown constrained cell proliferation, migration, invasion, and the Warburg effect in gastric cancer cells via inactivating the AKT and MEK/ERK pathway.