Background Although leukocytoclastic vasculitis (LCV) is often idiopathic or secondary to benign diseases, it sometimes accompanies malignancies. Besides being more common in hematological cancers compared to solid tumors, the association of acute lymphoblastic leukemia (ALL) with LCV is extremely rare. Case report In this study, we present a 22-year-old woman presenting with palpable petechiae, purpura, and ecchymoses on her limbs. Bone marrow and skin biopsy of the patient with bicytopenia revealed precursor B cell ALL and LCV, respectively. Conclusion This case is the first adult ALL case with paraneoplastic LCV. In this study, it is emphasized that hematological malignancies should be considered in patients presenting with cutaneous vasculitis, especially in the presence of cytopenia.