To determine the features of fibromyalgia (FM) in patients with rheumatoid arthritis (RA). Seventy-six patients participated in the study. The patients were divided into 2 groups: RA+FM (n=55), FM (n=21). Anamnesis of life and disease was carefully collected in all patients. The intensity (according to VAS) and phenotype (Pain DETECT, DN4) of pain syndrome (PS), the presence of symptoms of central sensitization (CSI), fatigue (FSS), signs of anxiety and depression (HADS), sleep quality (PSQI), cognitive functions (DSST) and quality of life (QoL) (EQ-5D, FIQR) were also evaluated. The average age of patients in the FM group was significantly lower (42 [35; 53] vs. 50 [42.5; 59], p=0.042). Patients with «pure» FM without RA were more often divorced and had no children (p=0.045 and p=0.02, respectively). The duration of PS in the groups did not differ (11 [7; 17] vs. 8 [5; 13] years, p=0.429), however, patients with «pure» FM waited longer for diagnosis (115 [40; 198] vs. 20 [5.5; 59] months, p<0.001), and they also were less likely to be recognized as disabled (p=0.003). Patients of both groups had equally severe fatigue, anxiety, depression, sleep disorders and cognitive functions compared to the norms. Patients of the FM group noted a lower QoL (according to EQ-5D, p=0.041) then in RA+FM group, despite the comparable severity of FM and the intensity of the PS in both groups. FM in patients with RA develops at a later age compared to «pure» FM. The clinical picture of FM with and without RA does not differ in the main manifestations, however, the QoL of patients with «pure» FM is lower. Accounting for fibromyalgia in the treatment of rheumatoid diseases can significantly improve the QoL of patients.