Endoplasmic reticulum stress (ER) is characterized by the accumulation of misfolded and unfolded proteins in the ER lumen, mostly in secretory cells, which, due to their functions, are rich in the ER. In response to stress, the eukaryotic cell has evolved adaptive mechanisms known as the unfolded protein response (UPR) whose main goal is to restore cellular homeostasis. Homeostasis is restored by stopping protein translation, activation of molecular chaperones, or degradation of misfolded proteins, and can lead to cell death. Unresolved chronic ER stress leads to pathological changes. Hepatocytes have large capacity for protein synthesis and they are highly exposed to possiiblities of ER stress. Activation of UPR pathways has an important role in the prevention of liver pathogenesis. Growing body of evidence connects ER stress with inflammation, cell injury, and steatosis in nonalcoholic fatty liver disease (NAFLD) where inflammatory cytokines and chemokines play a major role. The qPCR method (optimal reaction conditions and primers) was developed for C57Bl6Crl mouse strain liver tissue. ER stress was induced with single tunicamycin injection and expression of inflammatory cytokines, TNFα, MCP1, CXCL1, and the TFF3 protein, whose role in the liver is still insufficiently investigated, was examined. The results were analyzed by the REST 2009 software. ER stress induced statistically significant increased expression of Tnfα, Mcp1, and Cxcl1 genes while expression of the Tff3 gene was not significantly changed.