Objective: The present study aimed to analyze the risk factors for positive peripherally inserted central catheter (PICC) related fungal colonization in preterm infants. Methods: A retrospective study was conducted in a tertiary hospital in southwest China between January 1, 2018 and December 31, 2020. The enrolled infants who underwent ultrasound-guided PICC insertion during hospitalization were born at < 32 weeks gestation or birth weight < 1500 grams. The demographics, the PICC related characteristics, the use of antibiotic, glucocorticoid and parenteral nutrition (PN) were collected from the medical record. Univariate and multivariate analyses were performed to investigate risk factors for PICC-related fungal colonization. Receiver operating characteristic (ROC) curve was used to determine the optimal cut-off value by calculating the Yoden index. Results: A total of 124 premature infants underwent ultrasound-guided PICC insertion. Among them, 19 patients had positive results of fungi at PICC tips.PN infusion duration (OR 1.37, 95%CI 1.05-1.79) and postnatal glucocorticoid exposure(OR 9.19, 95%CI 1.04-81.65) were independent risk factors for fungal colonization in PICC. The optimal cut-off value was 15days,28days, respectively. Conclusion: PICC tips fungal colonization is affected by postnatal glucocorticoid exposure and PN infusion duration. Appropriate clinical management should be adopted to avoid fungal colonization and fungemia.