The three-day spring political party conference is expected to attract around 2,500 delegates.
The Lib Democrats were due to hold their autumn conference at ACC Liverpool in September this year, but had to move the date and venue to avoid a clash with the Scottish Referendum. The event will now take place in Glasgow.
The conference marks the Liberal Democrats third visit to Liverpool. The party held its spring conference in Liverpool in 2008 and returned two years later in September 2010 for its main autumn gathering.
Bob Prattey, chief executive of ACC Liverpool, home to BT Convention Centre and Echo Arena, said: "It was unfortunate that we were unable to accommodate revised dates this year due to our busy conference calendar and commitments to existing events but the return of the Lib Dems underlines the relationship we have built up with the organisers over many years.
"They have held two successful conferences with us so have the confidence and reassurance that we will deliver again."
The party has been working closely with Liverpool Convention Bureau to secure accommodation in the region.
The last time the party was in Liverpool for its main autumn gathering, Nick Clegg, Deputy Prime Minister and Leader of the Liberal Democrats, was joined by 6,000 delegates and 1,600 global media.
The event generated £10m for the local economy with 206 fringe meetings hosted at ACC Liverpool and around 300 additional fringe meetings taking place elsewhere in the city.
Lucy Hope, head of conference office at the Liberal Democrats, said: "We’re really excited about returning to ACC Liverpool. This is an important conference for the Party, the last before May 2015 elections, and we know that the fantastic facilities at ACC Liverpool, backed up by the hardworking and ambitious team there, will help us deliver a successful event. The commitment and enthusiasm the ACC Liverpool team and their partners demonstrate throughout our conference planning and execution is second to none."