Pyoderma gangrenosum (PG) is a rare but serious ulcerating skin disease that occurs either idiopathically or associated with various systemic diseases and malignant tumors. Although the association of PG with myeloid malignant tumors is well known, their association with lymphoid malignant tumors, especially in children is extremely rare. We present here a case of PG in a 4-year</span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> and </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">4</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">month</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> female child, </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">diagnosed</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> in the Pediatrics department, which had initially evolved well with oral corticosteroid therapy and a local dermocorticoid. The development was marked 7 months after stopping corticosteroid treatment by the occurrence of acute lymphoblastic leukemia.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">This case of PG is presented in the intention of increasing awareness of this uncommon condition with may oc</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">c</span></span></span