To examine the application effect of ultrasound-guided placement of midline catheter and to select the appropriate placement method of intravenous catheter for patients with oral and maxillofacial tumors.We retrospectively analyzed the general data and venous catheter-related information of 143 oral and maxillofacial tumor patients who received treatment between June 2019 and December 2021. There were two patient groups, a control group of patients with inserted peripheral venous catheters (PVC) and an observation group of patients with midline catheters placed under ultrasound guidance. We made a comparative analysis of the incidence of catheter-related complications, including bleeding at the insertion site, phlebitis, catheter blockage, extravasation, etc., in the two groups. When the baseline data from the two groups were not balanced, we used propensity score matching (PSM) to match the general data before comparing the complication incidence between the two groups.There were 71 patients who underwent 215 times of PVC placement in the control group and 72 patients who underwent 72 times of midline catheter placement in the observation group. There was no significant difference between the patients in the two groups in terms of age, sex, diagnosis, or the use of anticoagulant medication ( P>0.05) . The observation group had longer average length-of-stay than the control group did ( P<0.01). The cost of catheter placement in the observation group was 1080 yuan per set, with the average daily cost being about (56.27±20.23) yuan. Patients in the control group had PVC placement for an average of (3.03±0.93) times. The cost for PVC placement was 96 yuan per time and the average daily cost was about (19.94±7.50) yuan. There was significant difference in the average daily cost between the observation group and the control group ( P<0.01). PSM was performed for the two groups. Before PSM, the incidence of catheter-related complications in the observation group (8.3%, 6/72) was lower than that of the control group (30.2%, 65/215) and the difference was statistically significant ( P<0.01). After PSM, 72 times of catheter placement from each group were included in comparative analysis. The incidence of catheter-related complications in the observation group (8.3%, 6/72) was lower than that of the control group (54.2%, 39/72) and the difference was statistically significant ( P<0.01).Patients have low incidence of catheter-related complications when they have midline catheter placed under ultrasound guidance, which helps reduce the pain of repeated venous insertion that patients incur and the workload of clinical nurses. The use of midline catheters is appropriate for and should be popularized among patients with oral and maxillofacial malignant tumors, especially patients who have poor peripheral venous conditions and those who are undergoing repair and reconstruction surgeries.Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).