Objective: To investigate the relationship between serum Incretin and acne vulgaris (AV) and insulin resistance (IR), and to find the biological indicators of acne vulgaris with insulin resistance. Methods: 60 patients diagnosed with acne vulgaris in the dermatology department of Zagazig University and 56 healthy people in the health examination center of this hospital were collected, respectively, as the control group; all the included people were drawn fasting blood to test serum Incretin, blood lipids, sex hormones and INS release test to explore the role of serum Incretin in acne vulgaris and insulin resistance. Results: The average level of Incretin in the acne group was lower than that in the control group, and the difference was statistically significant (t = 7.189, p < 0.001). The average level of Incretin in the acne group with insulin resistance was lower than that in the acne without insulin resistance group, the difference was statistically significant (t = 22.328, p < 0.001). In the acne group, the insulin resistance index decreased with the increase of Incretin level, and the two showed a negative correlation. (R = -0.711, p < 0.001). Conclusions: Patients with acne vulgaris are prone to have insulin resistance. Insulin resistance in patients with acne vulgaris is negatively correlated with Incretin. Serum Incretin may be expected to be a biomarker for diagnosing acne vulgaris patients with insulin resistance. The severity of acne vulgaris may have no obvious correlation with insulin resistance and serum incretin.