The impact caused extensive damage, pushing the ambulance off the roadway where it then rolled.
An 87-year-old patient and a 65-year-old nurse died at the scene, while two other passengers had to be cut out of the vehicle by Queensland Fire and Emergency crews.
The 41-year-old Brisbane man has been charged with two counts of dangerous operations of a motor vehicle causing death.
He will face the Rockhampton Magistrates Court on Wednesday.
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