"When you compare and contrast to what AT&T announced in their earnings — they're bleeding. They're needing to go and find new revenue streams," he said on CNBC's "Squawk on the Street."
Legere's comments came after his company saw its stock jump more than 7 percent Monday after posting better-than-expected quarterly profit. The company also added additional postpaid customers. Additionally, the T-Mobile chief executive commented on AT&T's recent announcement of a deal to buy Time Warner.
"What they're doing right now is a vertical integration, it's an attempt to enter businesses and have adjacent revenue streams," he said. "What people shouldn't think they're going to be able to do, or would do, is hold content hostage, so only their users could view certain content. That would be the death of their overall business."
T-Mobile's stock is up more than 28 percent year to date.