Background: Systemic lupus erythematosus is an autoimmune disease. Parvovirus B19 infection can break tolerance to self-DNA and promote pathogenesis of autoimmunity and might induce either idiopathic SLE in a person who is genetically susceptibl or it might induce a SLE-like picture. Objectives: Detection of PV-B19 DNA and it's IgM and IgG antibodies in the serum of SLE patients and in apparently healthy volunteer in Benha University Hospitals. Methodology: The study was conducted on 60 subjects classified into 2 groups: Group I: Including 40 SLE patients fulfilling SLICC Classification Criteria , 20 of them were in exacerbation state and the other 20 cases were in remission state and Group II: Including 20 age and sex matched apparently healthy volunteers serve as a control group . All patients were subjected to full history taking, clinical examination and laboratory investigations. PV- B19 IgM and IgG were measured using anti PV- B19 ELISA kits and PV-B19 DNA was detected by using real time polymerase chain reaction (PCR). Results: PV- B19 DNA was detected in 9 cases (45%) with active disease, Out of the 9 patients with PV- B19 DNA, only 1 had positive PCR results alone , 1 had positive PCR and IgM results and 7 had positive PCR, IgM and IgG results. on the other hand, PV- B19 DNA was detected in only 1 case (5%) out of 20 remittent cases (p=0.003). Active cases were significantly associated with higher frequency of IgM and IgG when compared to remittent cases (p=0.010, 0.020, respectively).There was significant differences in SLEDAI between active and remitted cases (p