Moses, who joined the Blues from Wigan in 2012, played a bit- part role in his debut season at Stamford Bridge before two underwhelming loan spells at Liverpool and Stoke City.
Moses was widely expected to leave the London club this off-season, but Mourinho has surprisingly given his full backing to the Nigeria international and expects him to be a prominent figure this season.
"Victor is strong, he is experienced," he told reporters after the club's 4-2 pre-season defeat to New York Red Bulls. "He has got good competition but he is an experienced guy.
"He is fast, he is aggressive. He needs to learn to play with us obviously but I am happy with his week and his 45 minutes. Victor has had an evolution in the past couple of years."