Demireva did not reach the final at the
2006 World Junior Championships, but won the silver medal at the
2008 World Junior Championships. She was again knocked out in the first round at the
2011 European U23 Championships. At the senior level she finished eighth at the
2012 European Championships and seventh at the
2013 European Indoor Championships. She also competed at the
2013 World Championships without reaching the final. Her personal best jump is , achieved in June 2018 at the
Diamond League meeting in
Stockholm. ==Achievements==