2020 All-Ireland Under-20 Football Championship

The 2020 All-Ireland Under-20 Football Championship was the third staging of the All-Ireland Under-20 Championship and the 57th staging overall of a Gaelic football championship for players between the minor and senior grades. The championship ran from 7 February to 19 December 2020.

were the defending champions, but were beaten by in the Munster final.

The final took place on 19 December 2020, between and. Galway won the match by 1–11 to 0–13 to win their sixth title and their first since 2013.

's Ciarán Archer was the championship's top scorer with 1–25. Galway captain Jack Glynn was named U20 Footballer of the Year.

Player eligibility
At the start of the championship footballers aged under 20 cannot play for both their county's senior and under-20 championship teams. Initially a footballer must opt to play for either the senior or the under-20 team. Once a county's senior team exits the senior championship all of their under-20 players are then eligible to play for the county under-20 team.

This rule was introduced to prevent player burnout and avoid scheduling conflicts when the senior and under-20 championships are played in the same summer months as both county teams have distinct panels of players. Inevitably some county under-20 teams play without their best under-20 footballers as a result of the player eligibility rule.

Competition format
Provincial Championships format

Connacht, Leinster, Munster and Ulster each organise a provincial championship. Each province decides the format for their championship – the format can be straight knockout, double-elimination, a league, groups, etc. or a combination.

All-Ireland format

The four provincial winners play in two All-Ireland Under-20 Football Semi-finals, with the winners of those matches playing in the All-Ireland Final.