Travis Frain was "hit head-on" by a car on Westminster Bridge as the attack began on Wednesday, suffering multiple fractures to his hand and leg.
Prince Charles paid a visit to the 19-year-old from Lancashire, who is recovering in King's College Hospital.
The Edge Hill University undergraduate posted a picture on Facebook showing the prince at his bedside.
When a friend jokingly suggested he "could have dressed up" for his visitor, Mr Frain replied: "I do what I can, with what I've got hahah."
Mr Frain had been visiting the Palace of Westminster with 13 other students and a lecturer to watch Prime Minister's Questions.
He was walking across Westminster Bridge when he was mown down by attacker Khalid Masood's car.
Angela Frain, from Darwen, said her son escaped with his life after going over the bonnet of the car as the attack began.
Seconds later, the politics student, who wants to become an MP, called his mother to say: "Mum I'm safe... I know you will be worrying."
He needed an operation on his leg, doctors said.
He also suffered deep cuts and minor whiplash, but said: "At the end of the day, it could have been a hell of a lot worse."
Another student, 18-year-old Owen Lambert, needed stitches to a head wound, while two others received treatment for lesser injuries.
Four people died and 50 people were injured in the attack, with 31 receiving hospital treatment.
Attacker Khalid Masood, 52, drove his car on to the pavement and into pedestrians on Westminster Bridge, before crashing the vehicle into railings and running into the grounds of Parliament.
He was armed with a knife and fatally stabbed PC Keith Palmer, before being shot dead by police.
Police have made 11 arrests and 10 people are still being questioned.
The Prince of Wales has visited a student who was injured in the Westminster attack.