[6] El Hammamy lost to Satomi Watanabe in the quarterfinals of the girls under-13 final of the British Junior Open Squash 2012.

She reached quarterfinals of the 2015 Women's World Junior Squash Championships before being knocked out by compatriot Habiba Mohamed.

She reached semifinals at the 2016 Women's World Junior Squash Championships and was knocked out by Rowan El Araby from the tournament.

She also took part at the 2016 Women's World Open Squash Championship but lost to her compatriot Nour El Tayeb in the first round of the tournament.

[13] She rose to prominence after her stunning victory over eight time world champion Nicol David of Malaysia in the first round of the Windy City Open in 2018.

[15] Hania's triumph was considered as a massive upset in squash arena as it marked Nicol's first defeat in the first round of a competitive World Series tournament in nearly 16 years.

[19][20][21][22] In December 2019, she broke into the top 10 rankings after her impressive performances during the CIB PSA Women's World Championship where she reached semifinals.

In March 2020, she won her first platinum tournament at the age of 19 after defeating her compatriot Nour El Sherbini in the final of the Black Ball Squash Open.

[33] In May 2023, she reached the semi final of the 2023 PSA Women's World Squash Championship, before losing to the number 1 seed Nouran Gohar in 5 games.