She replaces Alison Haislip, who gave viewers a behind-the-scenes look at The Voice during the reality competition's first season.
Milian revealed the news on her Twitter account and promised to keep Voice fans updated on all the latest news and gossip.
"I'm officially your eyes and ears behind and beyond the stage for The Voice so if you're a major fan you may wanna follow me," Milian tweeted.
Paul Telegdy, executive president of alternative programming at NBC, praised Milian as the ideal social media correspondent for The View because of her own pop music success.
Teledgy said: "Christina's extensive musical background and widespread recognition make her the perfect choice for the role of social media correspondent on The Voice.
"Her experience as a singer will provide a comfort level to our artists when they speak to her about the ins and outs of the competition."
Christina Aguilera, Adam Levine, Cee Lo Green and Blake Shelton will all return to coach the second season of The Voice, which premieres after the Super Bowl on February 5 on NBC.
> Kelly Clarkson: 'I'd love to audition for The Voice' - video
> Christina Aguilera not being axed from The Voice, says NBC
Watch Christina Aguilera and Maroon 5 perform 'Moves Like Jagger' on The Voice below: