Abstract: Objective To detect the levels of serum microRNA-217(miR-217) in atherosclerosis (AS) patients and evaluate its clinical value as a non-invasive auxiliary diagnostic molecular marker for AS. Methods A total of 63 AS patients (case group) who were diagnosed and treated at the Affiliated Hospital of Xuzhou Medical University were selected. Meanwhile, 22 age- and gender-matched healthy subjects (control group) were included. Their serum samples were collected for detecting serum miR-217 levels by quantitative real-time PCR. Logistic regression analysis was performed to investigate the correlation between serum miR-217, HDL-C, TG, and AS. Receiver operating characteristic (ROC) curves were plotted to assess the diagnostic efficiency of miR-217 for AS. Results Compared with the control group, the case group showed a significant decrease in HDL-C and a significant increase in TG, while serum miR-217 expression was significantly upregulated (P<0.01). Logistic regression analysis indicated that miR-217 significantly affected the occurrence of AS (OR=1.51, 95%CI:1.045-2.182, P=0.028). ROC curve analysis showed that when the cutoff value for miR-217 was 8.851, the area under the curve(AUC) for screening AS patients from healthy individuals was 0.931 (95%CI:0.871-0.991), with a sensitivity of 0.70 and specificity of 1. The AUC of serum miR-217 for diagnosing AS was higher than that of serum TG and HDL-C, and the AUC for the combined diagnosis of AS using miR-217, HDL-C, and TG was the highest. Conclusions AS patients present significantly higher levels of serum miR-217 than healthy individuals, and miR-217 is a potential auxiliary diagnostic molecular marker for AS.