Mihambo finished ninth at the 2011 World Youth Championships, then competed at the 2012 World Junior Championships and the 2013 World Championships, without reaching the final. She also won the gold medal at the 2013 European Junior Championships, and finished fourth at the 2014 European Championships. She won her first senior major event at the 2014 European Team Championships, setting the new championship record with a jump of 6.90 metres. In 2015, she won the gold medal at the European U23 Championships and finished sixth at the World Championships. She narrowly missed a medal at the 2016 Summer Olympics, finishing fourth, but won the bronze medal at the 2016 European Athletics Championships. In 2018, she finished fifth at the World Indoor Championships and became European champion. Mihambo won the IAAF Diamond League and became world champion in 2019. In 2021, she won the gold medal at the Summer Olympics in Tokyo with a jump of 7.00 metres, beating Brittney Reese and Ese Brume narrowly by 3 cm.