•Accurate cannulation is essential for extracorporeal cardiopulmonary resuscitation.•Japanese multicenter data were analyzed with propensity score matching.•Real-time ultrasound-guided cannulation was associated with shorter cannulation time. Extracorporeal cardiopulmonary resuscitation (ECPR), a bridge to treatments for cardiac arrest patients, can be technically challenging and requires expertise. While ultrasound guidance is frequently used for vascular access, its effects on cannulation time in patients treated with ECPR are poorly defined. We hypothesized that real-time ultrasound guidance would contribute to faster and safer cannulation for ECPR. This nationwide, multicenter, retrospective study analyzed data from 36 Japanese institutions. Patients who were over age 18 years and underwent ECPR between January 1, 2013, and December 31, 2018, were included. Patients who underwent open surgical vascular access were excluded. Cannulation time and outcomes of patients who underwent real-time ultrasound-guided cannulation (i.e., ultrasound-guided group) were compared to those cannulated without the use of real-time ultrasound guidance (control group) using propensity score matching analysis. The ultrasound-guided group comprised 510 cases, whereas the control group comprised 941 cases. Of those, 443 propensity score-matched pairs were evaluated. Cannulation time in the ultrasound-guided group was 2.5 minutes shorter than in the control group difference, −2.5 minutes; 95% Confidence interval (CI), −3.7 to −1.3, p < 0.001. The incidence of catheter-related complications and the incidence of the poor neurological outcomes (Cerebral Performance Category ≥3) did not differ between groups Odds ratio (OR), 1.51; 95% CI, 0.64–3.74; OR, 1.08; 95% CI, 0.83–1.59. Real-time ultrasound-guided cannulation was associated with shorter cannulation time of ECPR.