Barkley's stunning free-kick gave Everton a 2-1 win over Tiendalli and his Swansea team-mates at the Liberty Stadium on Sunday, further enhancing the 20-year-old's burgeoning reputation.
Barkley's mixture of guile and energy have marked him out as a candidate for inclusion in Roy Hodgson's national squad for next summer's finals.
And Tiendalli, whose prodded shot hit Bryan Oviedo for Swansea's equaliser after Seamus Coleman's opener, sees no reason why the Toffees starlet would not light up Brazil if Hodgson has the courage of his convictions to select him.
"Barkley is a very good player, everyone can see it, it is very clear," said the Dutchman.
"There is no reason he can't go to the World Cup. He is young but it does not matter, if you are good enough you are old enough and he could be a very important player for England."
Full-back Tiendalli also believes Everton have got what it takes to secure Champions League qualification.
"Of course they can finish in the top four," he said. "If they stick together and retain their form they will be top four.
"They play great football going forward and they are a very good side."
Defeat for Swansea summed up a frustrating first half of the season, where their usual fluid build-up play has not yielded a cutting edge in front of goal.
The 11th place Swans now face a challenging run of fixtures over the festive period, including meetings with Chelsea and Manchester City.
But Swansea head to Stamford Bridge on Boxing Day buoyed by memories of their win there in the Capital One Cup semi-final first leg last season.
And Tiendalli hopes it can start a good run for the Welsh club, who have won just two of their last nine games.
He said: "We have a very tough schedule - Chelsea, Aston Villa, Man City - and we have to start picking up points, starting on Boxing Day against Chelsea.
"It's going to be tough but we have confidence that we can pick up points
"We did well there last year and we are confident that we can beat anyone if we play 100 per cent. We must keep our head up even if it's not going good, we have to stay positive.
"Of course we are playing a good side but if we are 100 per cent we can be a dangerous team."