Objective: To evaluate obstetrical providers’ behaviours and maternal outcomes of women transferred with postpartum haemorrhage before and after introduction of a simulation-based training programme and standardised protocol Design: A retrospective cohort study Setting: All institutes operating deliveries in Satsuma Peninsula, Kagoshima Prefecture, Japan Population and Sample: Patients transferred with postpartum haemorrhage to Kagoshima City Hospital or Kagoshima University Hospital were included. Data collected before (period 1: 2015–2017) and after (period 2: 2018–2020) programme initiation were compared. There were 72 and 131 patients during periods 1 and 2. Methods: Data from medical records were used to compare providers’ behaviours and outcomes between the two periods. Main outcome measures: Effectiveness of the simulation-based training and standardised protocol in postpartum haemorrhage, change in providers’ behaviours, and maternal outcomes, including massive blood transfusion Results: Changes in providers’ behaviours were observed after the programme. The rate of shock index recording increased from 9.7% to 36.6% (p<0.001), and the rate of using intravenous lines ≥20 gauge increased from 91.7% to 100% (p=0.0017). The mean shock index on arrival significantly decreased from 0.85 to 0.77 (p<0.05). The massive transfusion (red blood cells ≥ 10 units) rate significantly decreased from 43.1% to 26.0% (p<0.05). Clinical factors related to massive transfusion were programme attendance, blood loss, and coagulopathy. Programme attendance reduced the risk of massive transfusion, while blood loss ≥2,200 g increased the risk. Conclusions: Introducing the simulation-based training programme and using a standardised protocol changed the providers’ behaviours and decreased the massive transfusion rate for postpartum haemorrhage.