Lubis was born on 7 March 1922 in Padang, West Sumatra to Raja Pandapotan Lubis, a high-ranking civil servant, and his wife. He was the sixth child of twelve.
As a child, Lubis wrote children's stories which were published in Sinar Deli, a Medan-based newspaper. When he was an adolescent, Mochtar Lubis often trekked into the jungles of Sumatra. Lubis later wrote that two events during this period, seeing a well-built yet abandoned hut and having a close call with a tiger, served partly as his inspiration for Harimau! Harimau!
After graduating from high school, Lubis worked as a teacher in Nias, North Sumatra. However, after a year he left for Batavia, where he worked at a bank. When World War II broke out and the Japanese occupied Indonesia in 1942, Lubis began working for the Japanese, translating international news for the Japanese army.
After Indonesia declared its independence in 1945, Lubis joined the Indonesian news agency Antara as a reporter. With Antara, he covered the Asian Relations Conference in 1947. During this same period he wrote Jalan Tak Ada Ujung and joined the Indonesian Visual Artists Association.
Lubis in c. 1955
In 1949, Lubis cofounded Indonesia Raya, later serving as the daily's chief editor. His work with Indonesia Raya led to him being imprisoned numerous times for his critical writing, including in Madiun, East Java, from 1957 – 1966. In 1955, while editor of Indonesia Raya, Lubis hosted the African American author Richard Wright during his three weeks in Indonesia to attend the Bandung Conference. Indonesia Raya published several articles related to Wright during April and May 1955.
On 4 February 1975, Lubis was arrested in relation to the 1974 riots during the visit of Japanese Prime Minister Kakuei Tanaka; Indonesia Raya was also shut down not long after the riots due to their reporting of the Pertamina corruption scandal. Lubis spent over two months in Nirbaya prison without trial and was released on 14 April 1975. He noted that other prisoners, such as former Indonesian Air Force chief Omar Dani, had been imprisoned without trial for years.
Lubis founded and co-founded numerous magazines and foundations, including the Obor Indonesia Foundation in 1970, Horison magazine, and the Indonesian Green Foundation. Lubis was also outspoken about the need forfreedom of the press in Indonesia and gained a reputation as an honest, no-nonsense reporter. In 2000, he was named as one of the International Press Institute's 50 World Press Freedom Heroes of the past 50 years.
After a long struggle against Alzheimer's disease Lubis died in Medistra Hospital on 2 July 2004 at age 82. He was buried next to his wife in Jeruk Purut Cemetery. His funeral was attended by hundreds, including journalists and writers Rosihan Anwar, Aristiddes Katoppo and Ramadhan KH.
He was born into a penniless family in Johore, and had worked as a coolie and served as a policeman when he was young. He was good at writing traditional Pantun poems. His career began in 1946, and he was a nucleus member of Angkatan Asas 50. Usman Awang died of heart attack on 29 November 2001 in Kuala Lumpur. He was buried at Bukit Kiara Muslim Cemetery, Kuala Lumpur.