The aim of this paper is to investigate the clinical features and transformation of elderly male patients with normal blood glucose levels at fasting and 2 hours after glucose intake but with hyperglycemia (⩾ 11.1 mmol/L) 1 hour after oral glucose tolerance test (OGTT-1h HG). Seven years of follow-up visits were performed on 189 elderly male outpatients with OGTT-1h HG and data was recorded on their body mass index (BMI), blood pressure, serum cholesterol and triglyceride test results and on their glucose tolerance changes every 1–2 years after taking OGTT; their possible causes were analysed. Follow-up visits revealed that 19 patients with OGTT-1h HG were diagnosed with diabetes (10.1%), 78 patients with impaired glucose tolerance (IGT, 41.3%), 2 patients transformed to normal glucose tolerance (NGT, 1.1%) and the remaining 90 patients (47.6%) remained unchanged. Synchronized comparison with IGT patients showed that the ratio of OGTT-1h HG patients turning to diabetes was lower than that of IGT patients (21.1%, χ ² = 13.05, P < 0.01), and the ratio of OGTT-1h HG patients transforming to NGT was slightly higher (0.4%, χ ² = 2.46, P > 0.05). The prevalence of complications of hypertension, coronary heart disease, cerebral vascular diseases and dyslipidemia in patients with OGTT-1h HGwere higher than those with NGT (P < 0.05) and were similar to that of IGT patients. As a special phenotype of OGTT and as part of an abnormal glucose tolerance conformation, patients with OGTT-1h HG warrant special attention, since about half of them were found to have developed diabetes or IGT, and their risk of suffering from vascular diseases were also increased.