Kane boasts 26 goals for Tottenham this term, having scored twice at QPR on Saturday, and is expected to be named in Roy Hodgson's senior England squad for matches against Lithuania and Italy at the end of March.
Pearce feels a call-up would be fully deserved, but insists the striker should still be utilised at Under-21 level at the end of the domestic campaign.
The former England Under-21 coach told BBC Radio 5 live's Sportsweek programme: "The message coming out of his mouth at the moment is suggesting that he wants to go to the Under-21 tournament.
"Personally, and I've championed this all along, I think the key to the senior squad being successful is to make sure we win trophies at the younger age group.
"The only way you do that is you take your strongest possible squad to the Under-21 and the Under-19 tournaments."
Tottenham head coach Mauricio Pochettino believes a break from football would do Kane more good, and plans to discuss the situation with the Football Association.
Yet Pearce added: "If you want to put a good argument against it - Lionel Messi and Cristiano Ronaldo - they don't rest these players. They play every game.
"I never ever hear either of the players suggesting that they want to miss an Olympics or a World Cup, or even playing in the younger age groups when they were coming through at the same age as Harry Kane."
