Depay has played a starring role in PSV's surge to the Eredivisie title this season and is the top scorer in the league with 20 goals to his name.
The Netherlands international - who also netted six goals in the UEFA Europa League this term - has been heavily linked with a move away from the Philips Stadion.
PSV technical director Marcel Brands revealed on Monday that Manchester United and Paris Saint-Germain are interested in Depay's services, with the Premier League club thought to be the front-runners for his signature.
And former Ajax, Barcelona and Netherlands star De Boer told talkSPORT: "He [Depay] is one of the biggest talents in Europe. He has skill compared to a young Cristiano Ronaldo.
"He is very lively, technically unbelievable, very skilful, very fast, he has a great goalscoring record, he can shoot from every distance - he has everything.
"For me, he is without doubt one of the best talents we have [in the Netherlands]."
Asked about the club that would be best suited to Depay, De Boer added: "I don't want to say which club is more suitable for him, but if he goes to United he knows there is a Dutch coach [Louis van Gaal] there who knows him from the World Cup. That is an advantage."
'Obviously Messi is the best player in history and being compared to him means that you're doing things right, but I try to be myself': Barcelona star responds to comparisons with Argentine legend
'Darwin Nunez would be gold for Arsenal': Liverpool legend claims Gunners should have signed Uruguayan striker in January
