A passenger wrote on Facebook that he had been on board at the time of the accident.
"I was thrown too, landing in front of her. I stayed with her and tended to her until [the] Fire brigade arrived and took over the care of her.''
He said the woman had a serious head injury, but was responsive.
The Fullers Group confirmed there was an incident on board their service to Devonport at 9.10pm, where the vessel "bumped'' into Devonport Wharf on arrival.
Chief executive Mike Horne said there were 50 passengers on board at the time.
"This resulted in a number of customers falling - one of which was taken to hospital.
"At this time, our priority is with the well-being of our customers and crew,'' he said.
"Safety is our number one priority within our business and incidents of this nature are taken incredibly seriously.''
As a result of last night's incident, an internal investigation into the circumstances is now underway and the appropriate authorities notified, Horne said.
The incident follows a more serious event in 2015, when 19 people were injured when a Fullers ferry slammed into a wharf at Devonport in February that year.
The company was this year ordered to pay more than $100,000 to the affected passengers, some of whom were thrown violently from their seats in the incident.
