Objective: This study aimed to assess the safety and effect on glucose level of <i>Bojungikgi-tang</i> in patients with type 2 diabetes mellitus.Methods: To review patients’ clinical characteristics and laboratory tests retrospectively, we investigated 15 hospitalized patients with type 2 diabetes mellitus who took <i>Bojungikgi-tang</i> at Kyung Hee University Korean Medical Hospital for at least one day between January 2012 and December 2022. The blood glucose levels, including fasting blood sugar (FBS), 2-hour postprandial glucose (PP2) levels, and glycated hemoglobin level, were collected to determine the effect of the <i>Bojungikgi-tang</i> on blood sugar changes. Furthermore, to evaluate the safety of <i>Bojungikgi-tang</i>, hepatic function and renal function tests were implemented, including aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, γ-glutamyltransferase, blood urea nitrogen, creatinine, and Modification of Diet in Renal Disease estimated glomerular filtration rate.Results: When <i>Bojungikgi-tang</i> and a standard treatment for diabetes were administered for patients with type 2 diabetes, it was confirmed that there were no statistically significant changes in FBS and PP2 levels in the analysis of each medication taken. There was no significant difference in the safety profile after taking <i>Bojungikgi-tang</i>.Conclusions: The combined administration of <i>Bojungikgi-tang</i> with standard hypoglycemic medication for patients with type 2 diabetes may not affect blood glucose levels and safety.