The unit has been placed outside Don Valley Academy on Jossey Lane in Scawthorpe, while others have also been installed across Doncaster Council’s Roman Ridge ward after a push by councillors.
Coun Leanne Hempshall said: “It came about when we realised the lack of defibrillators in the ward.
"There are now 3,000 known across Yorkshire and three have been activated and saved lives around Doncaster within the last few weeks.”
There are now four defibrillators in the Roman Ridge ward – at Cusworth Hall, opposite Aldi in Scawsby and at Amersall Court.
The defibrillators are available for public use 24 hours a day, seven days a week.
She said: “We were blown away by the support and the result was these CPADs (Community Public Access Defibrillators).
She added: “This all came about after a chat with Warren Bostock back in June last year.
"A ward resident who works for South Yorkshire Ambulance Service, he told me about the lack of CPADs in our ward.
"We started fundraising at Scawthorpe Community Centre and people really got behind it.
"The centre is run by a committee of dedicated volunteers who have recently created a hub and beating heart of the community - quite literally!”
Defibrillators are intended for use in emergency medical situations, providing electrical shocks designed to kick a victim’s heart back into life in the event of a heart attack.