The 24-year-old Mallorcan fell on turn 12 at the Circuit de Barcelona-Catalunya and was treated by medics before being taken to hospital where he underwent surgery.
“It is with great sadness that we have to report the passing of Luis Salom,” MotoGP said in a statement. “He underwent surgery but despite the best efforts of the trauma team he passed away at 1655 local time.
“Luis Salom will be remembered for his hard riding, his valiant Moto3 title challenges in 2012 and 2013 and his dedication to his family.”
The Spaniard made his world championship 125cc debut in 2009 as a wildcard at the Spanish Grand Prix and claimed his first career victory at Indianapolis in 2012.
Salom joined the Red Bull KTM Ajo team in 2013, winning four of the opening eight races, eventually finishing third in the championship — his best season.
This year he moved to the SAG team, finishing second in the opening round in Qatar.
Spanish MotoGP rider Dani Pedrosa tweeted: “Heartbroken by the loss of a great friend … we will always remember you”.
Compatriot Jorge Lorenzo, the 2015 MotoGP world champion, said: “I’m broken. Without words and very sad”.
Spanish Prime Minister Mariano Rajoy also expressed his grief.
“Saddened by the news,” he said. “My condolences and affection to the family of Luis Salom, his team and Spanish sport.” (Source: Reuters)