BACKGROUND: Whether radical surgery or simple cholecystectomy should be performed on patients with stage T1b gallbladder cancer re-mains controversial. To explore the effect of lymph node metastasis on the prognosis of patients with stage T1b gallbladder cancer is very crucial for guiding the treatment and follow-up of T1b gallbladder cancer patients. METHODS: A retrospective analysis of the surveillance, epidemiology and end results (SEER) database was performed. Patients with stage T1b gallbladder cancer that underwent surgery and pathologic nodal staging were identified. Logistic regression and Cox regression were performed to identify independent predictors and prognostic factors, respectively. RESULTS: Of 427 patients (age: 69.1 & PLUSMN;13.2 years, 72.1% females), 31 (7.2%) had lymph node metastasis. In multivariable analysis, higher histology grade was independent risk factor associated with the diagnosis of the patient lymph node metastasis. In the entire cohort, lymph node metastasis indicated a worse overall survival (HR [95%CI]: 3.83 (1.54-9.47), P<0.01) and disease-specific survival (HR [95%CI]: 3.46(1.54-7.82), P<0.01) in multivariable analysis. Lymph node metastasis, in multivariable analysis, showed statistical difference for worse OS (HR [95%CI]: 4.04(1.20-13.65), P=0.02) and DSS (HR [95%CI]: 3.25(1.10-9.57), P=0.03) in moderately differentiation group. CONCLUSIONS: Higher histology grade was an independent risk factor for lymph node metastasis. Lymph node metastasis was an independent prognostic factor of worse OS and DSS. Lymph node metastasis showed statistical difference for worse OS and DSS in moderately and advanced differentiation groups, a finding that could guide the choice of surgery.