SUMMARY OBJECTIVE: This study aimed to investigate the frequency of fatigue in geriatric patients with primary sarcopenia and to evaluate the relationship between fatigue and symptoms such as depression and sleepiness. METHODS: This case-control study was conducted between December 2020 and August 2021 in the geriatrics outpatient clinic of Istanbul University-Cerrahpasa. The European Working Group on Sarcopenia in Older People 2 criteria were considered for the diagnosis of sarcopenia. Demographic data, accompanying chronic diseases, comprehensive geriatric assessments, and laboratory values of the patients were noted. Scales used to assess fatigue in all participants include Fatigue Assessment Scale, Fatigue Severity Scale, and Fatigue Impact Scale and associated symptoms include Geriatric Depression Scale and Epworth Sleepiness Scale. RESULTS: The mean (standard deviation) age was 75.3 (7.1) for 51 primary sarcopenia (38 female) patients and 73.5 (5.8) for 51 control (37 female) patients. There was no significant difference between the two groups in terms of gender and age (p=0.822, p=0.171). The prevalence of hypertension was higher, and the level of education was lower in the sarcopenic group than in the nonsarcopenic group (p=0.017, p=0.013). Fatigue Assessment Scale, Fatigue Severity Scale, Fatigue Impact Scale total, Fatigue Impact Scale cognitive, Fatigue Impact Scale physical, and Fatigue Impact Scale social questionnaire scores were significantly higher in the sarcopenic group (all p<0.001). The Geriatric Depression Scale score was statistically higher in the sarcopenic group; however, there was no significant difference in the Epworth Sleepiness Scale score between the two groups (p=0.014, p=0.072). Multivariate analysis was performed on education level, hypertension, fatigue questionnaires, and Geriatric Depression Scale, which were found to be significant in the univariate logistic regression analysis. In the multivariate logistic regression analysis, only the Fatigue Impact Scale total was determined to be associated with sarcopenia [odds ratio 1.161, 95% confidence interval (1.084–1.242)]. CONCLUSION: In primary sarcopenia, there is mental and social fatigue as well as physical fatigue. Therefore, the prevention and treatment of sarcopenia in geriatric patients is important.