Leicester will face Serie A side Napoli, Spartak Moscow and Legia Warsaw in Group C of the 2021-22 Europa League.
West Ham, competing in the group stage for the first time, have been drawn against Dinamo Zagreb, Genk and Rapid Vienna in Group H.
Scottish champions Rangers will play Lyon, Sparta Prague and Brondby in Group A.
Celtic are in Group G with Bayer Leverkusen, Real Betis and Ferencvaros.
The first group stage matches will take place on Thursday, 16 September, while the final round of fixtures are due to be completed on 9 December.
This year's Europa League final will take place in the Ramon Sanchez Pizjuan in Seville on Wednesday, 18 May.
Leicester finished fifth last season to qualify for the Europa League for the second successive year, while West Ham secured a top-six finish to secure their place in the group stage for the first time.
The Foxes reached the last 32 of the Europa League last season before losing 2-0 on aggregate to Slavia Prague, who eliminated Rangers in the next round.
Steven Gerrard's side were beaten by Malmo in the Champions League third qualifying round earlier this month to drop into the Europa League qualifying play-off, where they edged past Armenian side Alashkert to clinch a group stage place in European football's second tier event for the fourth consecutive season.
Celtic have also reached the group stage for the fourth year in a row after surviving a second-leg scare to beat AZ Alkmaar 3-2 on aggregate.
Before the draw was made, Villarreal forward Gerard Moreno was voted Europa League Player of the Season 2020-21 ahead of Manchester United duo Bruno Fernandes and Edinson Cavani.
Draw in full
Group A: Lyon, Rangers, Sparta Prague, Brondby
Group B: Monaco, PSV Eindhoven, Real Sociedad, Sturm Graz
Group C: Napoli, Leicester, Spartak Moscow, Legia Warsaw
Group D: Olympiakos, Eintracht Frankfurt, Fenerbahce, Royal Antwerp
Group E: Lazio, Lokomotiv Moscow, Marseille, Galatasaray.
Group F: Braga, Red Star Belgrade, Ludogorets, Midtjylland
Group G: Bayer Leverkusen, Celtic, Real Betis, Ferencvaros
Group H: Dinamo Zagreb, Genk, West Ham, Rapid Vienna