Mr. Seferinoğlu was born on 25 July 1969 in Ardeşen, Rize, grew up in Ardeşen and completed his primary, middle, and high school education in this district. In 1991, Mr. Seferinoğlu received his bachelor's degree from İstanbul University Faculty of Law in which he had enrolled in 1987. He worked in İstanbul as a self-employed lawyer since 1993. Mr. Seferinoğlu was elected as a Member of Parliament from İstanbul in the 26th term in the general elections of 1 November 2015. He held offices as the Head of Türkiye-Turkish Republic of Northern Cyprus Inter-Parliamentary Friendship Group and a member of Committee of Justice of the Grand National Assembly of Türkiye. He held office as the Deputy Minister of Justice from 23 July 2018 to 25 January 2019.
He was appointed and took office as a Justice of the Constitutional Court on 25 January 2019.
Mr. Yıldız Seferinoğlu is married and has three children named Merve Gül, Furkan Safa and Meryem Bahar.