Prevalence rates of neurological complications in SLE patients as estimated by various authors range form under 20 up to 80%, most frequently reaching about 50%. These discrepancies result not only from the lack of a generally accepted classification of neurological symptoms typical of SLE, but also from difficulties in the differential diagnosis of organic and functional symptoms in this group of patients. Moreover, complications due to side effects of SLE treatment should be differentiated. The aim of the study was firstly, to estimate the frequency and character of neurological symptoms SLE patients, and secondly, to check if the presence of neurological symptoms is correlated with selected immunological parameter s (a-CL, p-ANCA, ANA, C3 and C4 fractions of complement). Participants in the study were 63 patients with SLE (58 women and 5 man), aged 17-63 (mean age 40.1 years). All the patients underwent a full rheumatological and neurological examination, supplemented with immunological assays and electrophysiological tests (EEG, EMG, BAEP, VEP). If necessary, in some cases CT and MR scans were performed. Neurological symptoms noted in 71.4% of the SLE patients turned out to be significantly more frequent in those with a high titre of anticardiolipin antibodies. No correlation was found between neurological symptoms frequency and a high titre of antinuclear antibodies, the presence of anticytoplasmatic antibodies of the perinuclear type, or the level of C3 and C4 fractions of complement.