The 17-year-old boy, named publicly only as 'Nahel M', was shot at a traffic stop in the Parisian suburb of Nanterre on Tuesday. The killing triggered consecutive nights of demonstrations across the capital and in other parts of France, many of which descended into violent clashes with police and vandalism and looting of businesses.
Protests have continued despite the police officer concerned being detained and charged with voluntary homicide on Thursday.
On Friday, Mbappe took to social media to appeal for calm on behalf of the French national team.
"Like all French people, we were marked and shocked by the brutal death of young Nahel," he wrote. "Firstly, our thoughts go out to him and his family to whom we extend our sincere condolences.
"Obviously, we cannot remain insensitive to the circumstances in which this unacceptable death has taken place.
"Since this tragic event, we have been witnessing the expression of popular anger whose essence we understand, but whose form we cannot endorse.
"With many of us coming from working-class neighbourhoods, these feelings of pain and sadness, we also share them.
"But to this suffering is added that of assisting powerless to a real process of self-destruction.
"Violence solves nothing, even less when it inevitably and tirelessly turns against those who express it, their families, loved ones and neighbours."
The statement concluded with a plea: "The time of violence must end to make way to that of mourning, dialogue and reconstruction."
Mbappe, who was raised in Paris suburb of Bondy, had on Wednesday expressed his heartbreak at what he called an "unacceptable situation", but given the escalation which has forced the French government to deploy 45,000 police officers, the call for calm from someone as influential as Mbappe will be welcomed by authorities.
Despite that, Friday night saw more unrest with the cities of Lyon and Marseille particularly chaotic. Mbappe and the government will be hoping his message helps defuse matters over the weekend.