Background and Objectives: Inadequate nutrition in patients on hemodialysis causes various complications. This study aimed to investigate the association between nutritional status and risk of osteoporosis, sarcopenia, and cognitive impairment in patients on hemodialysis. Methods and Study Design: We enrolled 131 older patients on maintenance hemodialysis. Geriatric Nutrition Risk Index (GNRI) was used to assess nutritional status. Patients were divided into quartile groups according to the GNRI. Dual-energy X-ray absorptiometry, bioimpedance analysis and handgrip strength measurement, and the Korean version of the Montreal Cognitive Assessment were used to assess osteoporosis, sarcopenia, and cognitive impairment, respectively. Biochemical laboratory tests were also performed before mid-week hemodialysis session. Results: Patients from higher GNRI quartiles had a lower prevalence of osteoporosis and sarcopenia. Cognitive impairment was not associated with any GNRI quartile. In the multivariable models, longer dialysis periods (OR 1.696, 95% CI 1.053-2.729, p=0.030) and higher intact parathyroid hormone levels (OR 3.136, 95% CI 1.781-5.518, p＜0.001) were significantly associated with osteoporosis risk. GNRI quartile 2 (OR 0.064, 95% CI 0.005-0.883, compared to quartile 1, p=0.040) and higher hemoglobin A1c levels (OR 3.728, 95% CI 1.033-86.4, p=0.043) were associated with a higher sarcopenia risk. Lower hemoglobin levels (OR 0.585, 95% CI 0.360-0.950, p=0.030) were associated with a higher risk of cognitive impairment. Conclusions: In patients on hemodialysis, inadequate nutrition was associated with the risk of osteoporosis and sarcopenia, but not cognitive impairment. Proper nutritional assessment and management in these patients could prevent complications related to bone and muscle loss.