The de Havilland Tiger Moth flipped and came to rest upside down.
A police spokesman said officers responded to a call at noon today and went to the Cromwell Racecourse airport near State Highway 6 and Ripponvale Rd.
There were no serious injuries, he said, but the road had been blocked and Fire and Emergency NZ assisted at the scene.
A Hato Hone St John spokeswoman said one person sustained moderate injuries and took themselves to hospital.
Warbirds over Wanaka general manager Ed Taylor said the plane had been in the region for a while and the pilot who flew it at the show was at the controls today.
He said two people were in the aircraft, which sustained some damage.
Mr Taylor earlier today told the ODT that no one was injured.
A photo of the crashed plane was posted on social media by Cameron Scott, who was on his way to Queenstown.
He said he was travelling past the racecourse airport when he noticed police, a fire crew and the Tiger Moth upside down.
In his post he said it was a ‘‘sad sight at the Cromwell racecourse around 12.15 today.
‘‘Tiger Moth overturned. Emergency services there, hope no-one was injured.’’