Objective To determine the hypoglycemic effect of pioglitazone and acarbose on the patients with type 2 diabetes mellitus (T2DM) and hypertension. Methods A total of 150 diabetic patients (82 males and 68 females, age ranging from 61 to 89 years) with coexisting hypertension admitted in Xijing Hospital from May 2011 to May 2013 were enrolled in this study. They were randomly divided into 2 matched groups (n＝75 for each group), and treated by pioglitazone and acarbose respectively. Before and at 12 weeks after treatment, their systolic blood pressure (SBP), diastolic blood pressure (DBP), glycosylated hemoglobin (HbA1c), tumor necrosis factor-α (TNF-α), adiponectin (APN), Homeostasis Model Assessment Insulin Resistance (HOMA-IR), albumin excretion rate (AER), left ventricular hypertrophy(LVH), peripheral blood CD34 and vascular endothelial growth factor receptor 2 (VEGFR-2) levels, CD34+/VEGFR-2+ endothelial progenitor cells (EPC), nitric oxide (NO) and nitric oxide synthase (NOS) were determined or calculated, and compared between the 2 groups. Results After 12 weeks treatment of pioglitazone, the patients had their blood pressure lower than 140/90mmHg, significantly different from the acarbose group (P＜0.05). The pioglitazone group had significantly higher APN levels, and obviously lower HbA1c, TNF-α and HOMA-IR when compared with the acarbose group (P＜0.05). Compared with acarbose treatment, pioglitazone treatment resulted in markedly reduced BUN, SCr, AER and LVH (all P＜0.05), but remarkably increased CD34 and VEGFR-2 levels, and NO and NOS levels (all P＜0.01). Conclusion Pioglitazone treatment results in decreased HbA1c and increased APN to reduce renal damage; induces to lower LVH to protect heart function; decreases serum levels of CD34 and VEGFR-2 to protect EPC; and improves the contents of NO and NOS to exert a protective role in the hardening process of arteries.