Objective: Familial Mediterranean Fever (FMF) is a disease characterized by recurrent fever and peritonitis. The onset of clinical symptoms and severity of disease in patients with FMF may be different according to the type of mutation. MEFV gene mutations and clinical symptoms were investigated in this study. The relationship between the genotype and phenotype of the disease was evaluated. Material and Methods: 110 patients diagnosed with FMF were included in this study. The first episode age and age at diagnosis were identified. The complaints during an attack were recorded. MEFV gene mutations were determined. The relationship between the type of mutation and mutations groups (homozygous/heterozygous/compound heterozygous) with clinical symptoms were investigated. Results: The most common mutations were M694V (43.6%), followed by V726A (13.6%) and E148Q (10.9%). Chest pain was the most common clinical finding in patients with the M694V/M680I heterozygous mutation (p<0.01). There was a significant relationship between homozygous mutations and arthritis and growth retardation (p=0.049). There was also a significant difference between age of onset of symptoms and time of diagnosis (6.94±4.15 / 8.69±4.20 years, p<0.0001). Delay in diagnosis of FMF was not associated with mutation type and whether the mutation was homozygous or heterozygous (p>0.05). Conclusion: We think that arthritis, growth retardation, and chest pain were associated with the type of mutation during attacks but the age of onset of symptoms was not associated with the type of mutation.