Alexis Mac Allister is an Argentine professional footballer who plays as a midfielder for Premier League club Liverpool and the Argentina national team.

Alexis Mac Allister was born on 24 December 1998 in Santa Rosa, La Pampa. Mac Allister's older brothers Francis and Kevin are also footballers. They are the sons of Carlos Mac Allister and nephews of Patricio Mac Allister, both retired footballers. Mac Allister is of Irish descent, tracing his ancestry to Donabate, in County Dublin, Ireland. Mac Allister also has Italian ancestry through his maternal grandmother.