The 17-year-old was crossing the road with three men when he was hit by a silver Mazda on Westmuir Street in the Parkhead area of Glasgow at around 5.10pm on Friday.
The teenager was initially taken to the Glasgow Royal Infirmary, but has since been transferred to the Queen Elizabeth University Hospital where medical staff describe his condition as serious and stable.
The men he was with were not injured.
The car drove off after the incident, however a silver coloured Mazda car was later found abandoned in Silverdale Street.
Police said the vehicle has been taken away for forensic examination.
Detectives are appealing for information about the incident as they try to establish exactly what happened and the motive behind it.
Detective Inspector James Biggam said: “This incident has left a young man seriously injured and it’s imperative we trace the occupants of the silver coloured car.
“We are still trying to piece together the exact circumstances of what has happened and the reasoning for it.
“I am appealing to the local community to get in touch with us. You may have witnessed the incident or you may have seen the silver car prior to the incident taking place and can provide us with information which could assist our enquiries.
“Please, if you have any information, no matter how insignificant, pass it on to police.”
Officers remain in the area and continue to carry out door-to-door enquiries.
CCTV footage from around the area is being examined for any additional information.
Anyone with information is asked to contact police on 101, quoting incident number 2880 of May 4, 2018, or call Crimestoppers on 0800 555 111 where information can be given anonymously.