Background: Sleep is an essential primary need where recovery occurs in the body and brain to achieve optimal health. Medical student’ sleep quality tends to be poor due to a more busy schedule of lectures and practicums than other study programs. Disruption of sleep will affect the formation of hemoglobin and erythrocyte index, which is the cause of anemia. Aim: Analyzing the relationship between sleep quality and hemoglobin levels and erythrocyte index in medical students at the Universitas Nusa Cendana. Method: An observational analytic study with a Cross-Sectional design conducted on MEDICAL students of the Faculty of Medicine and Veterinary Medicine, Universitas Nusa Cendana. Sleep quality data were obtained by filling out the Pittsburg Sleep Quality Index questionnaire. Hemoglobin levels and erythrocyte index were obtained through complete blood examination with a Hematology Analyzer on 54 samples that met the inclusion criteria. Sampling was done by using the Stratified Random Sampling technique. The results were analyzed univariately and bivariate using the Chi-Square test. Results: The prevalence of poor sleep quality is 68%. Anemia occurs in 35.2% of subjects, and the most morphological features of erythrocytes were normochromic normocytic (72.2%). Bivariate analysis with the Chi-Square test showed p = 0.028 (p < 0.05) on the relationship between sleep quality and hemoglobin levels and p = 0.037 (p < 0.05) on the relationship between sleep quality and erythrocyte index. Conclusion: There is a significant relationship between sleep quality with hemoglobin levels and erythrocyte index in medical students at Nusa Cendana University.