INTRODUCTION: Fabry disease is a chronic, progressive, and multi-system hereditary condition, related to an Xq22 mutation in X chromosome, which results in deficiency of alpha-galactosidase enzyme, hence reduced capacity of globotriaosylceramide degradation. OBJECTIVES: to evaluate the prevalence of Fabry disease (FD) mutations, as well as its signs and symptoms, among relatives of chronic kidney disease (CKD) patients diagnosed with FD during a previously conducted study, named "Clinical and epidemiological analysis of Fabry disease in dialysis centers in Brazil". METHODS: a cross-sectional study was carried out, and data was collected by interviewing the relatives of patients enrolled in the Brazil Fabry Kidney Project and blood tests for both Gb3 dosage and genetic testing. RESULTS: Among 1214 interviewed relatives, 115 (9.47%) were diagnosed with FD, with a predominance of women (66.10%). The most prevalent comorbidities were rheumatologic conditions and systemic hypertension (1.7% each), followed by heart, neurological, cerebrovascular diseases, and depression in 0.9% of individuals. Intolerance to physical exercise and tiredness were the most observed symptoms (1.7%), followed by periodic fever, intolerance to heat or cold, diffuse pain, burn sensation or numbness in hands and feet, reduced or absent sweating, as well as abdominal pain after meals in 0.9%. CONCLUSION: We found a prevalence of Fabry disease in 9.47% of relatives of CKD patients with this condition, remarkably with a 66.1% predominance of women, which contrasts with previous reports. The screening of family members of FD patients is important, since it can lead to early diagnosis and treatment, thus allowing better quality of life and improved clinical outcomes for these individuals.