The "distressing" incident happened in Didsbury, Manchester, as the fire engine was responding to an emegency.
Tony Hunter, Assistant Chief Fire Officer for Greater Manchester Fire and Rescue Service, said: “At 12.47am on Saturday 28 December 2019 a Greater Manchester Fire and Rescue Service fire engine from Withington station was involved in a collision with a pedestrian at the junction of Wilmslow Road and School Lane in Didsbury.
“The individual involved in the accident, which occurred at a road junction as crews were responding to reports of a building fire, received First Aid from our firefighters at the scene before being conveyed to hospital by colleagues from North West Ambulance Service (NWAS). GMFRS has been informed that his condition is described as stable at this time.
“There is currently a joint investigation taking place between Greater Manchester Police (GMP) and the Fire and Rescue Service to establish exactly what occurred and it is anticipated the investigation will conclude before the New Year."
He added: “This has been a distressing incident and our thoughts are with the individual concerned and his friends and family at what must be a difficult time.
"As a Fire and Rescue Service we are also working to support our firefighters who were on the fire engine at the time, some of whom are understandably shaken by what has occurred.
“Greater Manchester Fire and Rescue Service serves all communities across the city-region every single day of the year. The safety and wellbeing of the public, as well as that of our crews, is a priority and central to all the work we do.
"GMFRS will ensure that, if necessary, lessons are learned from what has occurred in Didsbury this morning and we wish the injured party a speedy recovery.”