Paul Owen, 33, who is originally from the Louth area but is currently of no fixed address, admitted causing serious injury by dangerous driving on January 6, 2020.
He was jailed for 12 months and banned from driving for three and a half years.
He was also ordered to pass an extended driving test before he can legally drive again.
The young girl, who was walking home from school, tried to jump out of the way but was struck by the car driven by Paul Owen and thrown onto the ground.
She was left badly bleeding from serious facial injuries as a result of the incident in Newmarket, Louth, and has been left scarred for life.
Owen then drove off leaving her lying on the road.
Passersby went to her assistance
Tony Stanford, prosecuting, said: “She had pressed the button and waited for the green man to appear so that she could cross safely.
“She did everything correctly. She started to cross the road and the traffic lights were on red.”
He said the girl heard a car and then saw it coming towards her.
She attempted to jump out of the way but was hit by the car and landed on her back and head.
Police traced the vehicle later but when Owen was initially interviewed he claimed he was at home in bed throughout the day of the incident.
Officers subsequently tracked down CCTV footage which showed Owen driving in Louth on the day of the collision.
He was interviewed again and accepted he was the driver saying he was distracted by another car pulling out in front of him and missed the red traffic light.
Recorder Michael Auty QC told him: “The lights were on red.
“You should have seen that and you should have stopped. One second earlier and she may well have suffered catastrophic or even fatal injuries. That is something that I cannot overlook.
“The girl was left at the side of the road quite seriously injured.
“You should have stopped but you didn’t. It was cowardly to drive away.
“Only an immediate sentence of imprisonment is appropriate in this case.”
George Wills, in mitigation, said that Owen is extremely remorseful for what he did.
“This was a momentary lapse of concentration which led to extreme and significant consequences which he entirely accepts could have been much, much worse.
“He suffers from extreme anxiety and panic descended. That is why he did not stop.”
Mr Wills urged that any jail sentence should be suspended and told the court: “A custodial sentence is going to send him spiralling down and he will come out much worse for it.”