Witnesses said Friday hundreds of villagers demonstrated outside the hospital run by the Salvation Army to demand the reinstatement of Dr. Paul Thistle.
The Toronto doctor has worked in the Chiweshe community medical facility, about 80 kilometres from Harare, for 16 years.
A church vehicle was overturned and riot police fired tear gas to disperse protesters on Thursday.
Thistle has been given until Sept. 1 to leave his post.
Witnesses said Thistle had disagreements with superiors over hospital development projects, but community leaders want him to stay.