This is a single arm, open label, phase 2 trial aimed to investigate the effects and safety of neoadjuvant CDK4/6 inhibitors in combination with endocrine for HR+/HER2- breast cancer. A total of 40 patients with stage II-III HR+/HER2- breast cancer will be enrolled. Six 4-week cycles of adjuvant therapy will be administrated.Premenopausal or perimenopausal patients should combine ovarian function suppression, including bilateral oophorectomy or treatment with gonadotropin-releasing hormone agonists.