BackgroundConstipation is a common complication in type 2 diabetes mellitus (T2DM), yet its impact on mortality remains unclear. This study aimed to investigate the association between constipation and all‐cause mortality in patients with T2DM.MethodsWe conducted a retrospective cohort study using data from the National Health and Nutrition Examination Survey (NHANES) 2005–2010. Mortality outcomes were ascertained through linkage to National Death Index records until December 31, 2019. The association between constipation and all‐cause mortality was assessed using weighted Cox proportional hazards regression models. Kaplan–Meier curves were then employed to visualize survival probabilities. Effect modification was explored through stratified analyses and interaction tests.ResultsOf 1,339 participants with T2DM, 146 (10.90%) reported constipation. During a median follow‐up of 10.75 years, 411 deaths occurred (57 in the constipation group, 354 in the non‐constipation group). Fully adjusted weighted Cox regression analysis revealed that constipation was associated with increased all‐cause mortality (HR 1.50, 95% CI 1.01–2.22, P = 0.04). Kaplan–Meier analysis demonstrated a significantly lower survival probability in patients with constipation (log‐rank P < 0.05). Stratified analyses and interaction tests corroborated these findings across various subgroups.ConclusionsConstipation is associated with elevated all‐cause mortality risk in T2DM patients. These findings suggest that constipation management may be an important consideration in improving long‐term outcomes for individuals with T2DM.