Abstract: OBJECTIVE  To explore the effect and mechanism of Zhu Lian's type Ⅱ inhibition needling technique on regulating polycystic ovary syndrome with insulin resistance (PCOS-IR) in rats.METHODS  40 female SD rats were randomly divided into normal group, model group, acupuncture group and medication group, with 10 rats in each group. The acupuncture group were given "Guanyuan" (CV4) and bilateral "guilai" (ST29), "Zusanli" (ST36), "Sanyinjiao" (SP6), and "Fenglong" (ST40) points by Zhu Lian's type Ⅱ inhibition needling technique for 30 min, once a day for 28 d. The medication group was given ethinylestradiol cyproterone of 0.18 mg/(kg·d) and metformin of 135 mg/(kg·d) by gavage, once a day for 28 d. HE staining was used to observe the changes of ovarian tissue. Fasting blood glucose (FBG) was measured by tail cutting method. Fasting insulin (FINS) was measured by ELISA, and insulin resistance index (HOMA-IR) was calculated. The protein expressions of IRS-1 and IRS-2 in ovarian tissue were detected by Western blot.RESULTS  Immunohistochemistry result showed that IRS-1 and IRS-2 proteins were expressed in ovarian interstitial cells, granulosa cells and primary oocytes. Compared with the control group, the ovaries in the model group showed polycystic changes, with more preantral follicles, and the number of granulosa cells in the model group was less than that in the control group, and FINS content and HOMA-IR in the model group significantly increased (P < 0.05), and the protein expressions of IRS-1 and IRS-2 in ovarian tissue significantly decreased (P < 0.05). Compared with the model group, the preantral follicles and antral follicles were observed in the acupuncture group and medication (metformin) groups, the number of preantral follicles was less than that of the model group, the number of granulosa cell layers increased, the morphology was more complete, and the arrangement was orderly; FINS content and HOMA-IR significantly decreased (P < 0.05), and the expressions of IRS-1 and IRS-2 protein in ovarian tissue significantly increased (P < 0.05). There was no significant difference between acupuncture group and western medicine group.CONCLUSION  Zhu Lian's type Ⅱ inhibition needling technique can improve IR in PCOS rats, which may be related to the benign regulation of IRS-1 and IRS-2 protein expressions in ovarian tissue.