Background. Henoch-Schonlein purpura (HSP) is a systemic vasculitis with multiorgan involvement. The scrotal involvement and its sonographic appearance are less well recognized than that of the kidneys and abdomen, and the reported incidence is varied. Objective. To review the incidence of significant scrotal involvement in boys with HSP and its sonographic characteristics. Materials and methods. Thirteen boys (ages 4-11 years) out of 87 boys diagnosed with HSP, over a 15-year period had significant scrotal complaints. Seven underwent sonographic evaluation to define the extent of scrotal involvement and because testicular torsion was being considered. Results. Scrotal involvement producing significant pain occurred in 15% of boys with HSP. The majority of boys had the diagnosis of HSP established before developing scrotal complaints. Sonographic findings consistently included an enlarged, rounded epididymis, thickened scrotal skin, and a hydrocele. The testes themselves were usually sonographically normal. Conclusions. Scrotal involvement in boys with HSP is not uncommon. The sonographic findings in the scrotum are sufficiently characteristic to allow distinction from torsion in most cases.