Objective: It is a known fact that FVIII related antigen (FVIII Rag) level is raised in systemic necrotizing and large vessel vasculitis but contradictory results exist in small vessel vasculitis. We therefore assessed the value of this parameter in children with Henoch- Shonlein Purpura (HSP).Methods: FVIII Rag, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were determined in 14 children with HSP. Control groups consisted of 6 children with juvenile rheumatoid arthritis (JRA), 3 children with systemic necrotizing vasculitis and 8 normal children.Results: FVIII Rag levels were significantly higher in children with HSP compared to JRA and normal controls and these levels did not correlate with either ESR or CRP levels.Conclusion: It can be suggested that FVIII Rag level can be used as a marker for vasculitis, irrespective of vessel size.