To assess nutritional status, the prevalence of nutritional risk, and nutritional support in hospitalized patients in Guangzhou, to determine gender or age associated differences in the prevalence of nutritional risk. A total of 2550 patients admitted during April to December 2008 from six departments (Gastroenterology, Pulmonology, Neurology, Nephrology, General Surgery and Thoracic Surgery) of four teaching hospitals were screened using the Nutritional Risk Screening 2002 tool. Overall prevalence of undernutrition and nutritional risk was 17.8% and 41.5%, respectively. The department of Pulmonology had the highest prevalence of undernutrition (28.2%) and nutritional risk (55.9%). The prevalence of nutritional risk was significantly higher in patients >= 70 years of age than patients <70 years (64.2% vs 32.6%, p<0.001). No gender difference in the prevalence of nutritional risk was observed in general. In total, 47.6% of "at risk" and 19.4% of "not at risk" patients received nutritional support. Parenteral nutrition accounted for 88.8% of the nutritional support. The present study documented the prevalence of nutritional risk defined by NRS2002 and inappropriate assignment of nutritional interventions in Guangzhou hospitals.