Objective To explore the clinical application of the pedicled omentum flap in breast reconstruction of breast cancer patients. Methods Between May 2013 and October 2017, 205 patients with breast cancer received modified mastectomy. The pedicled omentum flap was used to reconstruct breast at the same time. All patients were female with an average age of 34.9 years (mean, 26-58 years). The tumor located at left breast in 127 cases and right side in 78 cases. The diameter of the tumor was 2-5 cm (mean, 2.9 cm). The 120 cases of breast cancer were at stage Ⅰ and 85 cases were at stage Ⅱ; and 126 cases were invasive ductal carcinoma and 79 cases were invasive lobular carcinoma. The course of disease ranged from 10 to 92 days (mean, 38.5 days). The size of defect after tumor ablation ranged from 9 cm× 6 cm to 18 cm×12 cm; the size of pedicled omentum flap ranged from 18 cm×10 cm to 22 cm×16 cm. Results According to the anatomical basis, the omentum was divided into 4 types, including thin type (42 cases, 20.5%), medium type (133 cases, 64.9%), hypertrophy type (24 cases, 11.7%), and absence type (6 cases, 2.9%). All omentum flaps survived successfully and the incisions healed by first intention. All patients were followed up 6-74 months (mean, 24.5 months); 83 cases were followed up more than 5 years. The shape, texture, and elasticity of the reconstructed breast were good and no flap contracture deformation happened. Only linear scar left at the donor sites, and the function of abdomen was not affected. No local recurrence happened. Conclusion The pedicled omentum flap can be harvested safely and reliable, which is the one of ideal option for breast reconstruction in breast cancer patients.