Erythema Multiforme (EM) is a generally benign and self-limited acute cutaneous reaction, associated with Herpes Simplex Virus (HSV) infection. It is characterized by polymorphic "target" lesions in extremities and mucosal tissues. We report a 22-year old patient with papules, vesicles and blisters, which evolved to cover 90% of the body in three weeks. We performed a PCR study for HSV, which was positive in a crust. A skin biopsy and positive immunohistochemical stain for LT CD4+ were compatible with bullous EM associated with HSV. We underline the importance of pathological clinical correlation, reinforced by a virological study, in the diagnosis of this case with atypical symptoms. The laboratory findings confirmed literature descriptions with respect to the pathogenicity of EM associated with HSV.