The 23-year-old custodian represents the Sinsheim club's second piece of transfer activity ahead of the 2014/15 pre-season campaign, following confirmation of Pirmin Schwegler's summer switch from Eintracht Frankfurt last week.
'Looking forward to the challenge'
"With over 130 appearances to his name and his undoubted quality as a player, Oliver Baumann will give us even more stability," explained Hoffenheim sporting director Alexander Rosen. "As a person, we're in no doubt that Oliver will be a great fit for our team as well. We're really happy he's chosen to join us."
Baumann, who spent ten years in the youth ranks at Freiburg before making his senior debut on the final day of the 2009/10 Bundesliga campaign, was just as excited about the move.
"After 14 years at Freiburg, I'm looking forward to playing in new surroundings," he enthused. "Hoffenheim have set the league alight with their attacking game this season. I'll try to shore things up at the back and advance their style of play. I'm looking forward to the challenge."