Brendan Rodgers’ side have brought Awoniyi to Anfield from Imperial Academy in Nigeria after fending off reported interest from Porto and Monaco.
The 18-year-old is understood to have cost around £400,000 ($614,000, 547,371 euros) and will spend the rest of the season learning his trade on loan with Frankfurt in the German second tier.
“This is the biggest club in the world and I’m privileged to be here,” Awoniyi told Liverpool’s website.
“I’ll try to develop myself very well so that when I come back to Liverpool I’ll be able to add value to the team.
“When I’m in the red shirt, I will always give my very best to make the fans happy.”
Awoniyi is a current Nigeria Under-23 international and has also played for the Super Eagles at the Under-17 and Under-20 World Cups.
He first earned a call-up for the senior Nigeria squad in 2013.
Liverpool also announced that their striker Samed Yesil and midfielder Sergi Canos have both gone out on loan, joining Swiss side FC Luzern and Brentford respectively.
Yesil signed for Liverpool from Bayer Leverkusen in 2012, but has made only two first team appearance.
Canos has agreed a deal that will see him stay at Championship club Brentford until January 3.
The 18-year-old Spaniard, yet to make a senior appearance for Liverpool, joined the Reds in 2013 from Barcelona. – Agence France-Presse