OBJECTIVES: To estimate the direct all-cause healthcare resource utilization and costs in T2DM patients with chronic comorbid conditions in China. METHODS: The China Health Insurance Research Association (CHIRA) claims database includes cross-sectional healthcare data that is proportionally sampled and is nationally representative. A retrospective analysis was conducted using the CHIRA database of patients with a diagnosis of T2DM and its comorbidities (ICD-10) from 2014-2015.  Resource utilization parameters including hospital visits, medication usage and total costs were computed from the billing data. Descriptive analyses were conducted using the overall sample and within comorbidities subgroups; p-values of <0.05 were considered to be statistically significant. RESULTS: A total of 42,245 T2DM patients who had continuous hospital visit records were identified. There were significantly more patients with comorbidities than those without (27,274 vs 14,971, p<0.0001). T2DM patients with comorbidities accounted for significantly more annual all-cause total costs per patient than non-comorbid T2DM patients costs (¥16,564.23 vs ¥7,013.57, p<0.0001). A similar however significantly greater difference in overall healthcare costs was seen in the outpatient only subgroup (¥11,449.60 comorbid T2DM vs ¥3,615.35 non-comorbid T2DM, p<0.0001). As for the 15,621 patients who received inpatient care, between patients with comorbidities and no comorbidity, there was a significant difference in average total medication costs (¥15,481.83 vs ¥4,570.35, p<0.0001), glucose-lowering drug costs (¥2,571.64 vs ¥834.10, p<0.0001) and non-drug costs (¥13,944.12 vs ¥5,516.79, p<0.0001). CONCLUSIONS: This study, using local claims data at population level, demonstrates that significant numbers of T2DM patients are suffering from comorbidities associated with the disease, creating a potential catastrophic economic burden in China. This problem is progressive, and actions should be taken to address the unmet needs.