The Manchester United attacker has joined Barca on-loan for the season with an option to buy.
However, Barca still need to find room in their wage budget for Rashford's salary in order to meet LaLiga regulations.
Asked about the situation, the England international told Marca: "I'm not worried about my salary. I think it's an issue the club needs to resolve, and I'm confident it will happen.
"I'm focusing on training and being ready for the start of the season."
Rashford also said: "It was a good preseason, and we're ready for the start of the season. I've integrated quite well and am adapting to the team and the coach.
"I can play in different positions, score goals from all areas of the pitch. It's about being able to score from different areas. Hopefully we can make a step forward from last year and try to win the Champions League."
He added: "There are many great players here, but I knew that before I arrived. The quality is very high and so is the intensity, and that's what we need to maintain throughout the season."