El Shenawy began his career in the youth system at his hometown club El Hamool before moving to Al Ahly, joining the club at the age of fourteen in 2002. He failed to make a league appearance for the senior squad before being released by the club in 2009. Following his release, he joined fellow Egyptian Premier League side Tala’ea El Gaish. During his time with El Gaish, El Shenawy spent time on loan with Haras El-Hodood.

For the national team, El Shenawy represented Egypt at under-18 level and later played for the Egypt national under-20 football team in the 2007 African Youth Championship. From 2013, he received several call-ups to the senior Egypt side before making his international debut in a 2–1 friendly defeat against Portugal. He earned praise for his performance in the match, with national team goalkeeping coach Ahmed Nagy commenting “He had a great game; I am so happy with his performance He deserves to be with the national team.”

El Shenawy joined Petrojet in 2013. His form during the 2015–16 season, keeping a joint league high eleven clean sheets in twenty-two appearances including a run of seven matches without conceding, led his former club Al Ahly to attempt to resign him after attracting the attention of manager Martin Jol.

He rejoined Al Ahly in July 2016, establishing himself in the first team over Sherif Ekramy after keeping five clean sheets in seven matches during January 2018, including helping the side to a 1–0 victory over Al-Masry in the 2017 Egyptian Super Cup. He also recorded the highest percentage of clean sheets by any goalkeeper in the Egyptian Premier League. In his first four seasons, he helped the club win the Egyptian Premier League in consecutive seasons.

In May 2018, he was named in Egypt’s preliminary squad for the 2018 FIFA World Cup in Russia. He played in warm up friendly matches against Colombia and Belgium prior to the tournament and was chosen as the starting goalkeeper for their opening match of the tournament against Uruguay, winning only his fourth cap, ahead of Essam El-Hadary and club teammate Ekramy. He was named Man of the Match in the first match after making several saves during a 1–0 defeat however, he declined to accept the award in the players’ tunnel after the match due to its sponsorship by Budweiser and was only photographed with the award. As a Muslim, El Shenawy is forbidden from drinking alcohol. Teammate Ekramy and Egyptian team director Ihab Leheta later attempted to persuade him to accept the award as a “historic” prize but he again refused.