They were denied access to the premises of the building after security officials barred the main entrance.
The protesters reportedly belong to the "NotTooYoungToRun" movement that has been fighting for the right of young Nigerians to have more opportunities to elective positions.
After marching down from Unity Fountain, they were denied access to the NASS complex after security officials barred the main entrance.
The National Assembly is expected to debate the bill to lower the age requirement for running for public office today.
Last week, Speaker of the House of Representatives, Yakubu Dogara reaffirmed his support for youth inclusion in politics, saying that the House would live up to its promise to do all within its powers to pass the bill.
He said, "The young people should be informed that we made a promise and we will keep to our promise, by God’s grace.”
Sponsors of the bill, Hon. Tony Nwulu, Sen. Dino Melaye (Kogi West - APC) and Sen. Abdul-Aziz Nyako (Adamawa Central - APC) were spotted with the protesters.
The bill will alter Sections 65, 106, 131, and 177 of the 1999 Constitution (as amended), as it seeks to reduce the age of qualification for the office of the President from 40 to 35 years; Governor from 35 to 30 years; Senate from 35 to 30 years; House of Reps from 30 to 25 years; and the House of Assembly from 30 to 25 years.
Passage of the bill will also make it possible for an independent candidate to be able to contest in the country's elections.