This study was aimed to assess: (1) the additive diagnostic utility of diffusion-weighted imaging (DWI) and magnetic resonance angiography (MRA) over conventional MRI in detecting brain lesions in patients with acute primary neuropsychiatric systemic lupus erythematosus (NPSLE), and (2) the relevance of their findings to the associated NP manifestations. Included were 34 patients with acute NPSLE with mean age of 33.26 ± 10.14 years and duration of illness of 3.33 ± 1.71 years. Clinical interviewing and psychiatric and cognitive evaluations were performed by applying the criteria of the diagnostic and statistical manual of mental health disorders criteria (DSM-IV), Stanford Binet Subset Testing, Mini-Mental State Examination and Wechsler Memory Scale-Revised. Serologic tests included looking for antinuclear antibodies, anti-double strand DNA, anti-phospholipid antibodies. Radiologic evaluation included conventional MRI, DWI and MRA. One or more NP manifestations were diagnosed in 28 patients, in which cognitive deficits were reported with headache, psychosis and CVS. Anti-phospholipid antibodies were reported in patients with CVS. Twenty patients (71.43 %) with primary NPSLE (n = 28) had MRI abnormalities in which hyperintense signals at subcortical and periventricular white matter and at the junction between the gray and white matter represented 75 % (n = 15) and with headache (n = 6), psychosis (n = 6) and acute confusional state (n = 3) with and without cognitive deficits, respectively. Moderate-sized infarctions with restricted diffusion in the distribution of middle cerebral arteries were represented in 35 % (n = 7) and with CVS, of them, 71.43 % (n = 5) had beading and focal narrowing of carotid arteries were consistent with vasculitis. Brain atrophy represented 20 % (n = 4) and with psychosis. Compared to those with normal MRI, patients with MRI abnormalities were older (P < 0.050) and had longer duration of illness (P < 0.050). To conclude, although DWI and MRA are helping in more precise etiopathologic diagnosis compared to conventional MRI, but their relevance to the present NP manifestations is still limited.