Trippier has been regarded as one of the stars of the tournament, with England having progressed through to the semi-finals, where they will face Croatia on Wednesday.
The right wing-back has not always been a regular with Spurs, but Dier admits that he is delighted to see his compatriot receiving positive reviews from the media and supporters.
At a press conference, Dier told reporters: "He's had a fantastic tournament. I'm so, so happy for him I think it is fully deserved. I think this season and last season but especially this season at Tottenham he has come on so much.
"Maybe that has been noticed as much as it should have been. It is not so much of a surprise [to me] but think the level he has shown throughout this tournament has been incredible.
"His consistency – everyone is trying to compare him to [David] Beckham, which is obviously fantastic for him. His delivery, aggression both offensively and defensively. I think he has been fantastic, his consistency has been incredible and I think he fully deserves it."
Trippier has contributed one assist in four starts for the Three Lions at the World Cup.