Aim To investigate the correlation between atherogenic index of plasma (AIP) and the occurrence of coronary in-stent neoatheroma (ISNAM) after coronary stent implantation. Methods A total of 164 consecutive patients with coronary in-stent restenosis (ISR) who were admitted to the Department of Cadiology, Beijing Anzhen hospital and underwent coronary intravascular optical coherence tomography from January 2019 to December 2021 were enrolled. Patients were divided into ISNAM group (75 cases) and non-ISNAM (89 cases) based on the presence of ISNAM. AIP and other clinical features were compared between the two groups. Logistic regression analysis was used to evaluate the risk of ISNAM occurrence. The receiver operating characteristic (ROC) curve was used to analyze the predictive efficacy of AIP.Results The proportions of patients admitted for acute coronary syndrome (ACS) and patients with hypertension in the ISNAM group were significantly higher than those in the non-ISNAM group (P＜0.05). The glycated hemoglobin level in the ISNAM group was 1.1 times that of the non-ISNAM group (P＜0.05), and the AIP was 2.4 times that of the non-ISNAM group (P＜0.01). Logistic regressions analysis showed that longer duration since coronary stent implantation, hypertension, and elevated AIP were independent risk factors for coronary ISNAM. The area under the curve (AUC) of AIP for predicting neoatheroma was 0.664 (95%CI:0.561～0.767, P＝0.003). Conclusion Elevated AIP was an independent risk factor for ISNAM after coronary stent implantation. Beyond strict control of low density lipoprotein cholesterol, clinicians should also improve the overall lipid profile to correct metabolic abnormalities and enhance patient prognosis.