Ernesto Valverde's appointment at Camp Nou led to speculation Herrera may reunite with his former Athletic Club coach.
The 27-year-old has one year left on his current contract with the Old Trafford club, but there have been reports United are willing to double his salary to keep him.
And the midfielder has dismissed speculation surrounding a move, insisting he is happy where he is.
"There is nothing certain about Barcelona because I am very happy at United and I feel valued and focused here," Herrera said after his side beat LA Galaxy in a pre-season game.
The Red Devils beat the American side 5-2 as new striker Romelu Lukaku made his first appearance in Jose Mourinho's team.
Despite the high-profile signing of the Belgian, Herrera admitted he is disappointed that Alvaro Morata will not be joining, after Jose Mourinho ruled out a move for him.
"Of course I wanted to have Morata as a team-mate, he was very close because the two clubs negotiated," he continued.
"Too bad he is not with us, but I wish him well."