The Mossos d'Esquadra, the regional Catalan police, said the driver of the vehicle had been arrested and a spokesperson told AFP the incident appeared to be "accidental".
"The situation is controlled and in no case does it pose a risk to people inside the sports venue," said the Mossos on social media platform X.
After the match had begun an announcement was made inside the stadium saying the crash situation was "under control" and that there were "no serious injuries".
The Catalan emergency medical services said on X that 13 people had sustained injuries, none of them serious.
Barcelona are hoping to clinch the La Liga title with a derby victory over Espanyol.