Objective To explore the safety of neoadjuvant chemoradiotherapy combined with sphincter-preserving operation in treatment of locally advanced low rectal cancer. Methods The clinical data of thirty-four patients admitted into our hospital between June 2007 and June 2009 with T3 and T4 low rectal cancer treated by neoadjuvant chemoradiotherapy and sphincter-preserving operation were collected and analyzed retrospectively. Routine fraction of radiation was given with total dose of 40 Gy, five times a week, 2 Gy per fraction. Patients received oxaliplatin (150 mg/d1), plus folinic (100 mg/d1-3) and 5FU (750 mg/d1-3) for total 1 cycles started from the 4th week of irradiation. Operation was performed 4 weeks after neoadjuvant therapy. Results After neoadjuvant therapy, all patients underwent surgical resection with average tumor size decreased by 41.2%, tumor T stage decreased in 67.6% (23/34) patients, and lymph nodenegative change rate was 58.8% (10/17). One patient had liver metastasis and one had local recurrence, but without stomal leak. And 88.2% (30/34) patients showed good function of sphincter. Conclusions Neoadjuvant chemoradiotherapy in advanced lower rectal cancer patients has shown its efficacy in down-staging, which is safe without increasing operation complications when combined with sphincterpreserving surgery.