Sales of the console rose 96 per cent week-over-week, according to retail monitor Chart-Track.
The new Titanfall hardware bundle, which includes a download token for the game, accounted for over 70 per cent of all Xbox One sales during the week.
Chart Track said on Monday that the EA published shooter became the biggest release of 2014 to date.
Xbox One and PC versions of Respawn Entertainment's debut game launched on Friday, with the console version accounting for 94 per cent of first week sales. An Xbox 360 edition is set for release at the end of March.
Yusuf Mehdi, head of marketing and strategy for Microsoft's Xbox group, told Reuters last week. "We're making a big bet that Titanfall is going to be a blockbuster launch for Xbox. We don't have a sales forecast for the game to share, but we expect it to be big for us."
CVG's Titanfall review concluded: "Thrillingly chaotic and expertly tuned, Titanfall is a fairly orthodox FPS elevated to greatness by dozens of intelligent design choices." See what other critics thought of the game in our Titanfall review round-up.