Glomus tumors are uncommon, benign solitary tumors derived from the glomus apparatus. We report here a case of a malignant glomus tumor in an 8-year-old child presenting as a multilocular ill-defined radiolucency of the mandible. The lesion microscopically showed sheets of round basophilic cells with high nuclear-cytoplasmic ratio, indistinct cell boundaries, nuclear hyperchromatism and nuclear pleomorphism. Immunohistochemically, the tumor was positive for vimentin and smooth muscle actin.