Thiago André started athletics at the age of 14 and is coached by former Brazilian runner Adauto Domingues . In 2011, at the age of 16, he competed for the first time in the Brazilian youth championships over 300 meters and was able to achieve top places. In 2012 he competed over this distance at the U18 South American Championships in Mendoza , Argentina , where he was victorious in 8: 41.84 minutes. Another year later he started at the U20 South American Championships, also in Argentina, over 1500 and 5000 meters. He was able to win the gold medal over both distances. Two further silver medals are added at the U20 Pan American Championships.
In 2014 he competed in the U20 World Championships over the 800 and 1500 meters and finished fourth in both races. In 2015 he competed for the first time in an international championship at the Pan American Games in Toronto, where he was eighth over 1500 meters in 3: 43.71 minutes. In 2016 he qualified for the Olympic Games in his native Brazil, where he started over 1500 meters. In the preliminary run, he was eliminated in 11th place in 3: 44.42 minutes and ended up in 22nd place overall.
In 2017 he became the first Brazilian champion over 1500 meters. Over this distance he could not start at the World Championships in London. A few days earlier, he reached the finish line in seventh place in the final over 800 meters and thus celebrated his best result in an international championship race. In the following years he missed the qualification for major major events and increasingly began to compete in the hall. At the beginning of 2020 he set a new South American record with 3: 39.13 minutes in Toruń.