A decrease in the early morning fasting Respiratory Quotient (RQ) suggests that a starving condition is formed during night time. Previous studies have shown that early morning fasting RQ decreases with decreased renal function; however, these results are not sufficient in case of patients performing hemodialysis (HD). Therefore, we conducted a cross-sectional study to clarify the relationship between the early morning fasting RQ of HD patients, the interdialytic interval and the hemodialysis time schedule of HD patients. Using an indirect calorimeter, we measured the early morning fasting RQ of the following day 1, day 2, and day 3 after the implementation of HD of 9 hospitalized HD patients [3 male and 6 female subjects with a median age of 68 (interquartile range 65-68) years]. As a result of multiple comparisons, a significant difference was found between three day levels [The next day: 0.87 (0.85-0.90), 2 days later: 0.80 (0.79-0.84), 3 days later: 0.82 (0.79-0.83), p <0.05]. However, there was no significant difference within each day level. Our analysis, which was classified into 2 groups, namely: day HD (n＝4) and night HD (n＝5), found significant differences between three day levels only in the group that had undergone HD during day time [day HD group, next day: 0.90 (0.87-0.97), after 2 days: 0.80 (0.80-0.85), after 3 days: 0.81 (0.79-0.88), p <0.05]. The present study suggested that hemodialysis time schedule may affect the early morning fasting RQ values of HD patients.