T cell acute lymphoblastic leukemia (ALL) is an invasive disease with a higher incidence in children and adolescents. In terms of Immunophenotype, T-ALL is positive for CD2, CD7, CD34 and HLA-DR, and the level of these markers is increased with increasing age. In addition, the myeloid markers (CD13, CD33) are sometimes expressed in T-ALL. In this study, we introduce a rare case of a 28-year-old woman with T-ALL with aberrant expression of myeloid markers (CD13), without lymphadenopathy and with 94% blasts in bone marrow specimens. The patient has the rare karyotype of 46,XX del(7)(q11.2q22). The presence of del7 is a rare phenomenon in T-ALL.