Hyalinizing spindle cell tumor with giant rosettes (HSCTGR) is a rare sarcoma that was first reported by Lane et al. in 1997. Many authors subsequently described it as a variant of low-grade fibromyxoid sarcoma. We report a case of this tumor on the left knee of a 50-year-old woman. The behavior of the tumor was so indolent with deceptively bland appearance that it was initially diagnosed as benign lesion and was treated with marginal excision. Wide surgical excision of the tumor was performed immediately after the diagnosis of HSCTGR. The patient was alive with no evidence of disease 18 months after the surgery. The treatment of choice for HSCTGR is wide surgical excision and long term clinical follow-up to evaluate any evidence of local recurrence or metastasis.