Her first international success was at the 1976 in Montreal, where she won a silver medal, with a personal best of 1.91 m, and was beaten only by Rosemarie Ackermann's 1.93 m leap.

Simeoni struggled to regain her form in the following years, with a series of tendon injuries.

At 1984 Olympics, Simeoni carried the Italian flag at the opening ceremony in Los Angeles.

Here, she cemented her reputation as one of the greatest female high jumpers ever, in a thrilling duel with West German Ulrike Meyfarth.

On 8 June 2007, Antonietta Di Martino jumped 2.02 m, establishing the new Italian record for women.