But, Brazil were left sweating on Neymar's fitness after the Paris Saint-Germain star was carried away in tears with an apparent lower leg injury in the 21st minute.
Qatar had a chance to pull a goal back in the 96th minute after the referee penalised Ederson for a mistimed challenge following a VAR review, however, Boualem Khoukhi's spot-kick cannoned against the crossbar.
It was a lively first half in Brasilia, where two goals were scored, a penalty was overturned by the VAR and Neymar left the pitch in tears.
Qatar had won seven successive matches heading into the friendly but the Copa America guests were completely outplayed as Brazil hit the front in the 16th minute.
Dani Alves picked out Richarlison, who rose highest to head past Saad Al Sheeb for his fourth international goal.
Neymar, who was seen crying on the sidelines, was forced from the ground shortly afterwards and replaced by Everton.
That did not hamper Brazil, who doubled their lead eight minutes later through Jesus following some neat combination play with Richarlison.
Philippe Coutinho thought he had the chance to make it 3-0 after a handball inside the box six minutes before half-time, however, the referee overturned his original decision following a VAR review.
The second half saw the introduction of AC Milan star Lucas Paqueta and Ajax sensation David Neres and while the changes hampered the flow of the match, the result was never in doubt even after Qatar's stoppage-time penalty.
What does it mean? Brazil building towards Copa tilt
The Neymar injury was unwelcome news but Brazil still showed glimpses of their quality in a fairly routine outing against the 2022 World Cup hosts.
Alves was impressive down the flanks, while Brazil's forwards proved a handful as the South American giants extended their undefeated streak to nine games since the World Cup quarter-finals.
Jesus and Richarlison combine well
The two Premier League stars showed they can play together, especially in the first half. Richarlison played in Jesus with a well-weighted pass to put Brazil 2-0 ahead. With uncertainty over Neymar, the duo could have an even greater role to play during the Copa America.
Brazil waiting on Neymar news
Having already recovered from a knee injury ahead of the midweek clash, Brazil will be hoping Neymar's latest issue is nothing serious. With plenty happening on and off the pitch, Neymar is facing a fight to be ready for the Copa America on home soil.
Brazil will finalise their Copa America preparations at home to Honduras on Sunday before opening the tournament against Bolivia on June 14. Qatar, meanwhile, will not play again until they face Paraguay (June 16) in Copa America action.