Objectives: This study is to report a case of hypersensitivity vasculitis with petechiae improved by Jeoryoung-tangMethods: Petechiae was observed in the upper and lower extremities of the patient. The patient also complained of cystitis symptoms such as dysuria and residual urine. Since there were no other accompanying symptoms such as abdominal pain, bleeding, or joint pain, the patient was diagnosed with hypersensitivity vasculitis and Jeoryoung-tang was prescribed for about a month.Results: After administering Jeoryoung-tang for about a month, petechiae improved from 8 to 2 points, and cystitis symptoms also improved from NRS 7 to 2 points.Conclusions: Since it has been confirmed that Jeoryoung-tang was effective as the treatment of skin symptoms through this case, Jeoryoung-tang can be prescribed for patients with other type skin diseases. However, since it is difficult to generalize this single case, continuous follow-up studies should be conducted.