Objectives: Percutaneous transluminal angioplasty (PTA) is an important procedure to treat stenosis of vascular access. Recently, we found that the vascular access blood flow (VABF) measured immediately after PTA increased over time without additional procedure. Therefore, this study was conducted to identify the factors that cause a change of VABF after PTA. Methods: In our institute, VABF was measured using the ultrasound dilution technique immediately after PTA and following measurement was performed within 1 month from PTA. Among the PTA cases for 2 years from March 2018 to February 2020, the cases that had consecutive increases of VABF after PTA were screened and the cases of PTA at central vein were excluded.  Results: A total of 45 PTA cases were included. The median time from the measurement on day of PTA to following measurement was 22-day. The mean VABF on day of PTA and the following measurement were 796.9 ± 329.0 ml/min and 1105.1 ± 410.3 ml/min, in which the following VABF was increased significantly compared to measurement on day of PTA. In univariate analysis, balloon diameter of the balloon catheter that used in PTA procedure, serum uric acid, and graft (vs. fistula) were significantly associated to an increase in VABF (balloon diameter of β=89.6, p=0.007; serum uric acid of β=-54.0, p=0.013, for change of VABF; balloon diameter of β=15.2, p=0.003; graft (vs. fistula) of β=21.3, p=0.049, for percentage change of VABF). In multivariate analysis, balloon diameter and serum uric acid were remained as independent factors for change of VABF and balloon diameter for percentage change of VABF. Conclusions: Our study identified consecutive increases in VABF after PTA without additional procedure and suggested a relationship between the increase in VABF and the balloon diameter that used in PTA. The findings of this study raised an issue about timely measurement of VABF after PTA.