In this study, we examined the frequency of p-ERK1/2 and PI3K expression in gallbladder adenocarcinoma specimens by means of immunohistochemistry and attempt to elucidate the clinical and pathological significance of changes in the p-ERK1/2 and PI3-K/AKT pathways in gallbladder adenocarcinoma. The gene discussed is MAPK3; the disease is gallbladder adenocarcinoma.