De Jong is enjoying a fine start to life in LaLiga after swapping Eredivisie titleholder Ajax for Spanish champion Barca in the off-season.
The 22-year-old was linked to Premier League champion Manchester City prior to his €75 million ($120.1 million) transfer to Barca.
Happy at Camp Nou, Barca and Netherlands midfielder De Jong compared the Premier League and LaLiga.
"I used to think that LaLiga was the strongest football league in the world," De Jong told UK newspaper The Mirror. "You could see their dominance in European Cup competitions.
"The Spanish clubs always progressed a long way and often grabbed the main trophies, the Champions League and Europa League.
"But the Premier League has gained power over the past few years.
"When it comes to pure skills, LaLiga is better. But because of the sheer intensity, the English competition is at a slightly higher level."
De Jong has scored one goal and supplied two assists in 18 LaLiga appearances for LaLiga leader Barca this season.
Barca is two points clear of bitter rival Real Madrid heading into the New Year, Ernesto Valverde's side back in action away to Espanyol on 5 January (AEDT).