The move comes as a boost to La Liga's hopes of restarting the season in the middle of June.
By Sunday morning, Spain had recorded 6,391 cases and 196 deaths.
Zidane has been given a contract until June 2022, just nine months after he resigned at the end of last season.
Barca were under pressure after Atletico Madrid and second-placed Sevilla had both moved level on points with the Catalan giants.
Barca knew they just had to extend their record unbeaten streak to 41 La Liga matches to seal a seventh title in 10 seasons.
AFP Sports looks at five things we learned from week 17 in La Liga.
Spain's audiovisual law requires the television rights holder to provide a 90 second summary of sports events to other broadcasters.
"The Real Madrid board has decided to name Zinedine Zidane as coach of the first team."
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