Mona Riini was born in Ruatahuna and was educated at Huiarau Primary School and Turakina Girls’ College, Marton. She attended Auckland Teachers’ College from 1954-55 from which she graduated with a Primary Teacher’s Certificate. Riini worked as a primary school teacher, as a principal of a bilingual school and as an educationalist at Auckland College of Education. She was acting district adviser of Māori and Pacific Island education and resigned from the Ministry of Education after her husband died in 1998. She became the first Māori woman Moderator of Te Aka Puaho, the Māori Synod of the Presbyterian Church. Riini attended writing workshops for Māori teachers at Ruatoki and Rongomai in Auckland, and also participated in a workshop led by Joy Cowley. She won a national trophy for composing action songs in 1969 and received recognition for other original compositions at a Tuhoe Festival in the 1970s. Riina wrote Māori language children’s stories, skits, and plays. Her other literary work included articles on wairua Māori and Māori maths, poetry, and rap and other songs in Māori. She has written many short excerpts of traditional kōrero as introductions to units of work. Riini has stated: "My whanau, hapu - iwi have shaped my life from birth to now - Total Māori community - Tuturu Māori - Te Reo and traditions and custom practised. Forest Lore is my speciality."
- Correspondence from Katie Riini, 30 Sept. 2004.
- Correspondence from Mona Riini, 4 Dec. 1992.
- New Zealand Who’s Who Aotearoa. Ed. Alister Taylor. Vol. 1. Auckland, N.Z.: New Zealand Who’s Who Aotearoa, 1992: 243.
- "Te Whaea Hihita." Te Ao Hou 70 (n.d.): 8-12.
- Riini writes a tribute in Māori and English to Sister Annie Henry or Hihita, who, following a call of God, travelled to Ruatahuna in 1917 and remained with the Tuhoe people until 1948 when she moved to Ohope. Riini writes that when Hihita first went to Ruatahuna there were no modern amenities such as roads, cars, schools, doctors or shops - ‘in fact, she was the first Pakeha who dared to come to this valley and settle.’ Hihita performed many functions in the community: alongside her church work she was also teacher, doctor, nurse, lawyer and policeman. She travelled many miles on foot visiting homes and every Sunday she went to every pa to take Sunday School classes.
- "Aroha behind Walls." Communications - Outlook Magazine. Wellington, N.Z.: Presbyterian Church of New Zealand, 1982.
- "Te Hui a Tuhoe." Te Ao Hou 74 (1973): 2-4.
- Te Hauhake Taewa. Kopeopeo, Whakatane, N.Z.: Māori Publications Unit, 1980. Rpt. in 1992. In Māori.
- Te Whiuwhiu Taewa. Nga Pikitia Dianne Williamson [Illus. Dianne Williamson]. Whakatane, N.Z.: Māori Publications Committee, 1980. Rpt. in 1993.
- A Māori language reader about harvesting potatoes.
- He Kapua. [Auckland, N.Z.]: Te Puna, c. 1988.
- I Te Ata. [Auckland, N.Z.]: Te Puna, c. 1988.
- He Hahaka, He Teitei. [Auckland, N.Z.]: Te Puna, c. 1988.
- Taku Manu Tukutuku. [Auckland, N.Z.]: Te Puna, c. 1988.
- Te Ta Potaka. [Auckland, N.Z.]: Te Puna, c. 1988.
- Ngata. [Auckland, N.Z.]: Te Puna, c. 1988.
- Tawhirimatea. [Auckland, N.Z.]: Te Puna, c. 1988.
- Aku Whatu. [Auckland, N.Z.]: Te Puna, c. 1988.
- Te Timatanga O Te Ao. Auckland, N.Z.: Shortlands, June 1992.
- Nga Kete Wananga. Auckland, N.Z.: Shortlands, June 1992.
- Hatupatu. Auckland, N.Z.: Shortlands, June 1992.
- He Rakau Hei Waka. Auckland, N.Z.: Shortlands, June 1992.
- Te Moemoea A Kahukura. Auckland, N.Z.: Shortlands, June 1992.
- Te Kimihanga A Maui I Tona Whaea. Auckland, N.Z.: Shortlands, June 1992.