Tiss worked as a teacher at the Higher Institute of Languages in Tunis until 2011. After joining the Ennahda Movement, she was elected on 23 October 2011 as a Member of the Constituent Assembly. She was one of the youngest members of the Assembly, and in debates over the proposed constitution notably commented that it is impossible to fully define "Islam". When the constitution was passed she said it "institutionalized revolution in Tunisia" and when asked if it would improve her baby daughter's life, she said "Of course, and if it doesn't, she can change it."
Personal life
Tiss married in 2012 and gave birth to a daughter in 2013, whom she sometimes brought into the assembly.