The former Tottenham Hotspur, Chelsea and Manchester United boss stormed on to the pitch and approached the referee to protest a dubious Betis goal.
The incident occurred with the match at 2-2 with Alex Moreno awkwardly netting for Betis appearing to use his arm, but the referee did not disallowed the goal prompting Mourinho's strong reaction despite the friendly's relative insignificance.
Mourinho was shown a red card for his actions along with Lorenzo Pellegrini before Roma had two more players and two more assistant coaches dismissed and conceded two more goals to lose 5-2.
The Portuguese took over at Roma in the off-season, as the Giallorossi look to improve on last season's seventh-place finish in Serie A.
Roma commences its 2021-2022 Serie A campaign against Fiorentina on Monday 23 August.