Objective To construct a PICC related skin injury risk assessment index system for patients with hematological diseases, so as to provide an assessment tool for PICC risk management. Methods The item pool of PICC related skin injury risk index was formed based on literature review and multidisciplinary group discussion, then it was improved by conducting a two-round Delphi study, and the weights of the indexes were identified through hierarchical analysis. Results The response rates of the 2 rounds expert consultation were both 100%, the expert authority coefficients were 0.899 and 0.921, and the Kendall coordination coefficients were 0.245 and 0.380 （both P＜0.05）. The variation of indicators in the second round consultation were 0.04-0.24. The final risk assessment index system of PICC related skin injury in patients with hematological diseases consisted of 3 first-level indicators，15 second-level indicators，and 44 third-level indicators. Conclusion The constructed risk assessment index system is reliable and scientific, and it can be used for risk assessment and quality management of PICC related skin injury in patients with hematological diseases.