Steven Mcilquham was hit by a silver/grey coloured Volkswagen car around 9.30pm yesterday while he was crossing the road.
The driver initially failed to stop after hitting the teenager from Wishaw, North Lanarkshire, who was crossing Alexander Street, at its junction with Marshall Street.
A 20-year-old man has been arrested in connection with road traffic offences and released pending further enquiries.
A report on the incident will be sent to the Procurator Fiscal and the road remains closed while police carry out investigations.
Inspector Scott Sutherland, of Motherwell's Road Policing Unit, said: "Our thoughts are with Steven's family and friends at this very sad time.
"Our enquiries are ongoing to establish the full circumstances of the crash.
"I would ask that anyone who witnessed the crash or may have any relevant dash-cam footage to contact the police as soon as possible."