The Serbian defender was celebrating with his team-mates as Cesc Fabregas' dramatic late winner in the 1-0 triumph at Loftus Road sent Chelsea seven points clear of Arsenal at the top of the Premier League.
Cameras subsequently showed Ivanovic clutching his neck and photos have emerged of a lighter being aimed towards the defender.
Other objects were launched in the direction of Chelsea players and QPR - who remain in the relegation zone - say that any fan found to have been involved will face a stadium ban and potential police action.
A club spokesperson said: "The club is aware that objects were thrown by a small section of supporters towards the pitch following Chelsea's 88th-minute goal.
"The club takes the safety of all supporters and players very seriously and are currently reviewing CCTV footage of the aftermath of the goal in an attempt to identify those responsible.
"Whilst we understand that passions run high during derby fixtures, this is not the kind of behaviour the club condones in any way, shape or form.
"We take a zero tolerance approach to this sort of behaviour and, if the perpetrators are identified, they will be banned indefinitely from the stadium and, where appropriate, we will liaise with the Metropolitan Police.
"The club are awaiting communication from the FA following the referee's report and will work closely with them in ensuring something like this does not happen again."
