Palaeontologists initially thought that the bones of the dinosaur - Albertavenator - belonged to its close relative Troodon, which lived around 76 million years ago - five million years before Albertavenator.
Both dinosaurs walked on two legs, were covered in feathers, and were about the size of a person.
New comparisons of bones forming the top of the head reveal that Albertavenator had a distinctively shorter and more robust skull than Troodon, its famously brainy relative, researchers said.
"The delicate bones of these small feathered dinosaurs are very rare. We were lucky to have a critical piece of the skull that allowed us to distinguish Albertaventaor as a new species," said David Evans, Senior Curator of Vertebrate Palaeontology at the Royal Ontario Museum in Canada.
The new species has been named in honour of renowned Canadian palaeontologist Philip J Currie.
The research was published in the Canadian Journal of Earth Sciences.