Poor diet quality is one of strong predictors of subsequent increased mortality in hemodialysis patients. To determine diet quality and to define major problems contributing to poor diet quality in hemodialysis patients, a cross-sectional study was conducted between June 2009 and October 2010. Sixty-three hemodialysis patients (31 men, 32 women; aged 55.3 ± 11.9 years) in stable condition were recruited from the Artificial Kidney Center in Kyung Hee University, Seoul, Korea. Three-day diet records were obtained for dietary assessment. Mean adequacy ratio (MAR) is the average of the ratio of intakes to Dietary Reference Intakes (DRI) for 12 nutrients. Index of nutritional quality (INQ) was determined as the nutritional density per 1,000 kcal of calories. Overall diet quality was evaluated using the Diet Quality Index-International (DQI-I). Statistics were used to determine diet quality, comparing dietary intake to DRI. Dietary calories (21.9 ± 6.7 kcal/kg/day) and protein (0.9 ± 0.3 g/kg/day) were found insufficient in the participants. The overall intake of 12 nutrients appeared to be also inadequate (0.66 ± 0.15), but INQs of overall nutrients, except for folate (0.6) and calcium (0.8), were found relatively adequate (INQ ≥ 1). As a result of diet quality assessment using DQI-I, dietary imbalance and inadequacy were found to be the most problematic in hemodialysis patients. This study suggests that the main reason for insufficient intake of essential nutrients is insufficient calorie intake. Hemodialysis patients should be encouraged to use various food sources to meet their energy requirements as well as satisfy overall balance and nutrient adequacy.