Midfielder Lampard, who won 106 caps, announced his international retirement on Tuesday, two months after England’s humbling group stage exit at the World Cup.
However, Sky Sports pundit Thompson says Chelsea's all-time leading scorer, who is currently on loan at Manchester City from New York City, served his country well.
“It’s no great shock,” Thompson told Sky Sports News HQ.
“He’s made a fantastic extension to his career at New York City and Manchester City and I think he’s thought ‘enough is enough, I’ve done my bit. If I want to prolong my career I need to give my body the best chance I can to play football’.
“He’s been an absolute pleasure. At these new clubs they will realise they are playing with an icon of the game. To do what Frank Lampard has done, play at such a level and in such a manner, I find it astonishing.
“His goalscoring record for a midfielder, I don’t think that it will ever be equalled. It’s astonishing. What a great player.
“When all this is over and done with and he does retire from the game, we’ll look back at him as a stellar performer for England, for Chelsea and for West Ham.”
After making his international debut in a 2-1 friendly win over Belgium in 1999, Lampard found the net 29 times in an England shirt.
However, throughout Sven Goran-Eriksson’s reign there was continued debate about whether Lampard and Liverpool’s Steven Gerrard could play effectively together in the centre of midfield.
While Thompson concedes the combination never truly clicked, he doesn’t believe it will detract from Lampard’s standing on the international stage.
“Trying to pitch the both of them together never seemed to really work because at that particular time Steven was a rampaging central midfield player, so you couldn’t have both of them,” said Thompson.
“At times you didn’t see the best of them but I don’t think that will take anything away from what he’s done for England. You don’t make 106 appearances and think ‘well, things didn’t work out for me with England’. It’s a great record.”
Perhaps Lampard’s most significant lasting legacy, though, is his ‘goal’ against Germany in the 2010 World Cup, said former England centre-back Thompson.
With England trailing 2-1 in the last-16 clash, Lampard crashed a shot in off the underside of the bar, but the ball span back over the line and play continued.
Goal-line technology has since been introduced by FIFA, with the governing body’s president Sepp Blatter saying: "That [Lampard goal] was the moment for me to say, 'You can't afford for something similar to happen in the next World Cup'. We could say it is a historic day for international football."
Thompson said: “He’ll be remembered for the goal that never was. It changed the whole thing for FIFA, with it being in one of their tournaments, in a great game. He’s changed the way we use technology in matches.”