England goalkeeper Mary Earps saved a penalty in the shootout victory
Chloe Kelly, who scored the winning goal in the Euro 2022 final at Wembley last year, netted the deciding spot-kick and immediately ran over to celebrate with fans in the stands.
Brazilian substitute Andressa Alves had equalised in stoppage time to force the shootout after Ella Toone had given England a first-half lead.
It was a historic night at Wembley Stadium that saw the European champions sternly tested by Copa America winners Brazil, but ended with the familiar sight of captain Leah Williamson lifting a trophy.
The Lionesses were given their biggest test of the year by a talented, albeit injury-hit, Brazilian side but delivered more silverware as their momentum continues to gather pace before this summer's World Cup in Australia and New Zealand.
The shootout was a test of nerve and England came through it in another statement of their intent to deliver on the world stage in four months' time.
Wiegman had expected England to be tested defensively at Wembley and they certainly were as the young Brazilian side created numerous chances in the second half, seeking an equaliser.
England had controlled play from the first minute in front of 83,132 fans watching on expectedly in London, with Lauren Hemp and Alessia Russo's movement particularly effective in the first half.
They deserved their half-time lead and looked fully in control until Brazil made changes at the break and began to show their credentials in attack.
Barcelona forward Geyse caused all sorts of problems and came close to scoring for the visitors when goalkeeper Mary Earps tipped her long-range effort on to the crossbar.
England were hanging on in stoppage time until Earps, who was formidable throughout their Euro 2022 victory, made a rare error, fumbling a cross which fell at the feet of substitute Alves and she fired it into the roof of the net.
But the Lionesses, who have shown mental resilience in abundance under Wiegman's management, regrouped to win the shootout 4-2 and lift their second trophy of the year, having retained their Arnold Clark Cup crown in February.
It was the perfect challenge before the World Cup and a timely reminder that England are not invincible, even though it has felt that way at times in the last 12 months.
There was plenty to get excited about by England's performance in the first half as their attacking play was free-flowing, creative and effective.
There is competition for places up front and Lauren Hemp showed why she should be starting with her movement down the left causing problems for Brazil.
Toone, who has gone from super-sub to starter since the Euros, also took her opportunity to cement her place in midfield in the absence of injured Chelsea star Fran Kirby and got a goal to show for her efforts.
However, the second half showed England still have some improvements to make in defence - although they did react to Brazil's more direct approach as the game wore on.
They appeared to have weathered the storm before Alves' late equaliser but Wiegman will be encouraged by their response to deliver in the shootout.