The frequency of dining out has rapidly increased; however, the independent associations between dining out, metabolic syndrome risk factors and nutritional status have not been well characterised. The aim of the present study was to investigate the associations between dining out, nutritional intakes and metabolic syndrome risk factors among Korean adults, using data from the 2011 Korean National Health and Nutrition Examination Survey. Frequency of dining out was significantly associated with intake of nutrients such as energy, water, protein, fat, carbohydrate, Ca, Na, vitamin A and carotene. Especially, the result revealed that Korean adults had insufficient Ca intake compared with the Korean reference intake (700 mg). As the frequency of dining out increased, so did energy intake. In addition, individuals who dined out seven or more times per week experienced a 64 % higher likelihood of blood pressure abnormalities, an 88 % higher likelihood of waist circumference abnormalities, and a 32 % higher likelihood of low HDL-cholesterol levels than those who dined out less than once per week. BMI was not associated with the frequency of dining out. Our findings suggest that strategies to modify dining-out behaviour could reduce metabolic syndrome risk factors via improved nutrition.