Inge Johanne Hagerup was born in Bergen and grew up in Nordfjord, Askvold, and Slagnes on Sunnmøre. She sat her upper secondary school leaving examination in Volda in 1924, worked for a year as a governess in Finnmark, then attended Treider business school in Christiania, working in an office and writing poems in her spare time. She married the lecturer and writer Anders Hagerup in 1931 and had two children. She was a political radical and member of the socialist group Mot Dag, working for the periodical Kvinnen og tiden from 1946 to 1956 and for the Communist Party newspaper Friheten from 1946 to 1949. From 1973 to 1976, she was editor of the alternative children's magazine Maurtua.
She made her debut as a poet with the collection Jeg gikk meg vill i skogene, 1939, and wrote altogether nine poetry collections, the last one being Fra hjertets krater, 1964. Her poetry collection Videre was published in Sweden in 1944 during the occupation of Norway. In Norway, she is particularly cherished for her committed poetry of political resistance, but she is also known for her love poems. Her works often have an intense and ironic timbre, and she uses a rigid, traditional form and plain language. She has also written short stories, radio plays, memoirs, children's books, and innovative and original children's poetry: Så rart, 1950, Lille Persille, 1961, and Den sommeren, 1971.