The 36-year-old, who spent seven years at Old Trafford, is convinced United boss Jose Mourinho will build on their Europa League success next season, and could even emulate the great Sir Alex Ferguson.
"Jose Mourinho showed in his first season what he can do," Park told the Daily Mirror.
"The league table was not what we want, but he qualified for the Champions League, and he also brought us the Europa League trophy.
"He can bring the team to the same level as before under Sir Alex Ferguson. He has great experience and he showed his qualities in his first season.
"Next season he will know all the players better and hopefully he can continue to improve because there was a period after Sir Alex Ferguson retired when the club struggled.
Park, now a global ambassador for United, picked up four Premier League titles in his time at the club, and was part of the side that beat Chelsea in the 2008 Champions League final in Moscow.
And the former midfielder believes that Mourinho could lead United to the final again as early as next year.
"They won the Europa League last season, which will give them confidence in the Champions League,” he said.
"Some of those players already have experience of playing in the Champions League too. With the quality of players they have, they can aim for the semi-final or final. They can target that, they can aim high.
"One of the big things about Jose is that he has great experience in the big leagues, in Spain, in England, in Italy and in Portugal.
"That is a big advantage for the club and Jose knows how to deal with the other clubs, like Real Madrid, like Barcelona. He knows how they play and how best to stop them."
