The Reds, who overcame Manchester City 5-1 on aggregate in the quarter-finals, will host Roma on 24 or 25 April before the return leg on 2 May.
Liverpool won the first leg 5-2.
Liverpool have been handed a major boost after Adam Lallana was named in the squad for the Champions League semi-final second leg clash with Roma.
Lallana has been missing for over a month after sustaining a hamstring injury at Crystal Palace.
There were fears that the England midfielder would miss the remainder of the season, and he had even been sent to South Africa for rehabilitation.
But Jurgen Klopp confirmed Lallana’s return to training in recent weeks and his inclusion in the 23-man travelling party to Rome is a major boost.
Liverpool have Emre Can and Alex Oxlade-Chamberlain sidelined, with only Jordan Henderson, James Milner and Gini Wijnaldum the other fit senior midfielders.
Joe Gomez misses out on a place in the travelling squad after sustaining an ankle injury against Stoke City on Saturday, but Trent Alexander-Arnold is fit enough to be involved.
Sadio Mane is also fit to travel after missing the clash with Stoke.
Liverpool squad: Karius, Clyne, Van Dijk, Wijnaldum, Lovren, Milner, Firmino, Salah, Henderson, Klavan, Moreno, Mane, Lallana, Mignolet, Robertson, Ings, Solanke, Jones, Ward, Woodburn, Masterson, Camacho, Alexander-Arnold.
Roma star Radja Nainggolan is taking optimism from the fact his side managed to eliminate Lionel Messi and Luis Suarez as they look to overturn a three-goal deficit against Liverpool in the Champions League.
Liverpool blitzed Roma in the first leg at Anfield last week and appeared to be easing into the final after going 5-0 up.
Roma gave themselves a glimmer of hope by scoring two late goals, however, meaning a 3-0 win in Rome on Wednesday will be enough to send them through to the final.