Mourinho was speaking before last night's Europa League defeat to Real Betis.
"He is doing a very good job," he said of Dybala.
"He knows his players perfectly and he knows that from the midfield onwards, Argentina has a lot of options but for me Dybala is one of the best players in the world.
“Dybala has taken this responsibility to be an important player for Roma. He has the tranquillity of great players and I think that with the 60,000 at the stadium, he will be at the top."