It was suggested on Twitter that Larsson, whose father scored 242 goals for the Gers' Old Firm rivals Celtic, was a target of the Rangers manager.
However, the 53-year-old denied the speculation, having already batted away rumours that he was set to sign former Arsenal and Manchester United hitman Robin van Persie.
"I don't know where they [rumours] come from. I honestly don't know where they come from," said Warburton to Rangers TV after Larsson's name was mentioned.
"It's football and it's about opinion, but there's no substance whatsoever."
Warburton's denial comes days after Larsson himself poured cold water on the Rangers link, taking to Twitter to say "are you having a laugh?" when asked about the rumours.
Larsson junior, 19, has netted eight times in 46 outings for Swedish side Helsingborgs.
Rangers may not be signing him, or Van Persie, but Warburton has still enjoyed a fantastic summer on the transfer front, taking nine players to Ibrox - including Joey Barton and Niko Kranjcar, to name a few.