The Belgian won the PFA Player of the Year award, despite City not winning the Premier League last term.
De Bruyne managed 20 assists and valuable goal contributions during a stellar season.
The playmaker is City's key player as they look to win back the league and finally win the Champions League this season.
"He is a masterclass player, one of the best players I have ever trained in my life," said Guardiola in a new documentary about De Bruyne's career, 'Made in Belgium' by City TV.
"Right now, he is the best. Right now, in the midfield position, he is the best."