Gary Smith of Byram, Knottingley, hit Kaitlin Mitchell, 12, as she was crossing the road after getting off her school bus on West Acres in Byram on September 28, 2017.
Miss Mitchell, who suffered serious head injuries, was airlifted to Leeds General Infirmary but never recovered, despite having emergency brain surgery.
She died in hospital a week later.
Smith, who fled in his Vauxhall Astra following the accident, tried to cover his tracks by making a 999 call to police, claiming his car had been stolen from his driveway, which was just a few metres away from the scene of the collision.
However CCTV cameras caught him driving through Knottingley and parking his car in a car park behind Yorkshire Bank.
Smith claimed he was unpacking his boot, when someone stole the keys which had been left in the car and driven away.
However he was filmed making his way over to a supermarket and ordering a cab to take him home.
A police officer who went to his address to take a statement about the 'stolen car' suspected he had been drink -driving and breathalysed him.
After failing the breath test, Smith admitted he was the driver of the car, which had struck Miss Mitchell. Later in custody a drug test revealed 170ug benzoylecgonine in his system, a derivative of cocaine.
Smith was jailed at York Crown Court for five years and nine months after pleading guilty to causing the death of Miss Mitchell by driving without due care while over the limit for alcohol.
He was also charged for drink and drug-driving, failing to report an accident, failing to stop after an accident and attempting to pervert the course of justice.
Dave Barf, Senior Investigating Officer said: “The decision Smith made on that day in September 2017 has caused an utter tragedy.
“To drive with both alcohol and illegal drugs in your system is an inherently selfish act. That this led to the death of a young girl with her whole life ahead of her is horrific.
"To then lie to police in an attempt to cover up the crime is not only selfish, but also despicable and cowardly.
“The sentence passed today will not bring Kaitlin back. To have a child, and sister, loved so much by her family cruelly taken away is completely heart-breaking.
"However, I do hope that today provides Kaitlin’s family with some form of closure and allows them to begin to move forward with their lives.
A commendation was awarded by the Judge to Traffic Constable Mark Mullins for his role in the investigation.