[1] Hajiji was born in Kampung Serusup, Tuaran as the second of three children of Noor Harun and Teruyah Omar (both now deceased).

[citation needed] Hajiji entered politics in 1990 as he contested in the 8th general election as a candidate for Sulaman state constituency representing United Sabah National Organisation (USNO) and subsequently won.

[citation needed] He joined United Malays National Organisation (UMNO) in 1994 following the dissolution of USNO.

He remained as an Assembly Member for Sulaman for six terms and is currently serving the seventh term after defeating two other candidates from Sabah Heritage Party (Warisan) and Love Sabah Party (PCS) in the recent state election.

He later joined Malaysian United Indigenous Party (BERSATU) in 2018 and serves as the State chairman for Sabah since 2019.

[9] On 29 January 2023, Hajiji Noor announced to lead Sabah People's Idea Party (PGRS).