The Catalan club reached an agreement with the midfielder for an immediate contract termination, making room for other players.
The 33-year-old Spaniard was on loan at Girona last season and did not train with the Catalan side on Wednesday, as his departure was being finalised.
Barcelona terminate Romeu's contract
Freeing up Romeu's contract and salary will allow Barcelona to register more players in LaLiga, including a summer signing who was on FC Porto's radar, Roony Bardghji. This departure also clears the way for the registration of defender Gerard MartÃn.
The Catalan club has already registered new signings Joan GarcÃa and Marcus Rashford ahead of their opening match against Mallorca, which Joan Laporta praised Deco for. The Swede and the left-back are next in line.
Following that, Barcelona will also attempt to finalise the registration of Wojciech Szczesny. For that to happen, Iñaki Peña will need to leave, with a loan move to Como reportedly close.
Romeu is expected to re-sign with MÃchel's side, this time as a free agent, according to AS, via Sportal, although he also has offers from other Spanish league clubs and from MLS.