The 18-year-old Englishman arrives on a long-term deal, reported to be five-years, for an initial fee of £3.5 million.
Liverpool activated a release clause in the England under-19 international’s contract and he underwent a medical at the club on Friday.
Gomez is primarily a centre-back but has also played at both right and left back for Charlton. He made 24 appearances for the Championship club last season, scoring once.
The 6′ 1″ defender is very highly rated, with Arsenal and Man City having also shown interest in him.
Gomez told the official LFC website: “It’s a dream come true. It’s a bit surreal and it hasn’t really hit me yet. But I’m buzzing and just excited to get started.
“The club has got great history and it’s a great club, and one that I’ve always been following from when I was young.
“The style of football and the top players here was somewhere that I wanted to go and get better and learn, and play good football. It was an easy decision.”
A profile on Gomez in the Daily Mail described his style as:
Those observing his game have compared him to Vincent Kompany and Rio Ferdinand at the same age. He is composed on the ball but athletic in the tackle.
Despite playing in a physical Championship at a tender age he has coped well, being described as level-headed, humble, and a model professional.
Gomez is expected to be loaned out for next season, with Derby County a likely destination after the successful loans of Andre Wisdom and Jordon Ibe in recent seasons. They appointed former Real Madrid assistant manager Paul Clement as their new boss this summer and would be a good coach for Gomez to learn from.
Gomez is Liverpool’s fourth confirmed signing of the summer, following James Milner, Danny Ings and Adam Bogdan.
Welcome to Liverpool, Joe.