He was born on 01.03.1980 in Demirci, Manisa. Roots from Derecikören village of Sındırgı of Balıkesir province, Dağ graduated from Simav Atatürk Primary School in 1990 and from Simav İmam Hatip High School in 1996. She studied at Dokuz Eylul University Faculty of Law and graduated from this school in 2000. Then, between 2000-2001 he completed his trainee lawyer. In 2004, he and his 2 friends opened the Law Office affiliated with the Izmir Bar Association. He has been working as a self-employed lawyer since 2004. In 2004, He is one of the five people who founded the Change Attorneys Group, which is important for having a different voice for the first time in Bar elections in Izmir.
During his university years, Hamza Dağ, who actively took part in the National Youth Foundation student branches, served as the chairman of the faculty, the campus and the university.
Dağ, who continued his social and political studies after his professional life, worked in various non-governmental organizations where he worked on human rights.
Hamza Dağ’s the first political party experience is in the AK Party. He served as a member of the Board of Directors of İzmir Provincial Youth Branches, as the Provincial Deputy Chairman in charge of Election Affairs of İzmir Provincial Youth Branches, then, he was elected as the chairman of the Provincial Youth Branches at the 3rd Ordinary Congress of the Ak Party Izmir Province Youth Branches on February 3, 2008.
With on June 12, 2011 Elections, he was elected as the İzmir deputy. In 25th and 26th terms, he also was elected to İzmir Deputy, and he held different positions in the parliament.
Dağ, who was elected as a reserve MKYK member at the 4th Ordinary Congress of the AK Party, he has entered MKYK instead of opening memberships together with the elections on 30 March 2014 and he was appointed deputy minister of the electoral unit. Subsequently, he was elected as a member of the MKYK at the the AK Party 5th and 3rd Extra Ordinary Congresses.
He is married and has three children. He speaks English and Arabic at intermediate level.