She trained under her uncle and future husband, Mustari Natanegara, and later performed for republican troops during the Indonesian National Revolution.

Over a five-year span, she appeared in thirty films, founded her own production company, and became one of the most popular Indonesian actresses of her time.

[8][2][9] While attending junior high school in Bandung at the age of 15, Sumarni began studying acting under her uncle, Raden Mustari Natanegara, who was 16 years her senior.

[10] They married in 1948, reportedly as an act of revenge against her lover, an Indonesian military officer who had cheated on her with Natanegara's wife, according to author Rd.

[11][12] After marriage, Sumarni left school and began a career as a stage actress, performing for troops during the Indonesian National Revolution until she eventually moved to Jakarta with her husband.

[18] On 7 August 1959, Sumarni, reportedly in a state of depression, was seen walking barefoot through the streets of Bandung, causing a traffic jam.

[17] In an interview, Sumarni later explained that she felt sad and confused, as she couldn’t remember where the Priangan residential police station was.

[17] Sumarni was said to be depressed over her failed attempt to sue her lover, Muhammad Jahja Ali, whom she claimed was the biological father of her child.

[17] After being found depressed and sick, Sumarni was cared for by a pedicab driver, who took her to a shaman named Mamah Atjeng for treatment.

[3] On 13 June, Harian Selecta reported that Sumarni's death was due to complications from a long-standing illness, compounded by continuous bouts of diarrhea, which led to dehydration.

[21] With her husband's permission, she entered the industry in 1951 through an acquaintance, Harun Al-Rasyid, an employee at the Golden Arrow Film Company.

Sumarni made her feature film debut in Golden Arrow's Seruni Laju,[4] followed by roles in Kino Drama Atelier's Kenangan Masa and Gadis Olahraga (both 1951).

[9] After the death of Dr. Huyung, the manager and director of Kino Drama Atelier, Sumarni was contracted by Djamaluddin Malik's Persari.

[23] In 1952, Sumarni starred in five films, including Si Mientje, Satria Desa, Terkabul, Pengorbanan, Pahit-Pahit Manis, and Apa Salahku, often being cast in romantic roles alongside S.

[9] Sumarni's first production with Bintang Surabaja was the musical comedy Putri Solo (1953), which became a major commercial success, breaking box-office records across the country.

[25] Reportedly, President Sukarno's favorite actress,[15] Sumarni was dubbed the "Queen of the Silver Screen" following a survey conducted by several magazines, including Kentjana and Dunia Film, in 1954.

[12] After retiring from the film industry, Sumarni became a businesswoman, investing her money in shares of a hotel and a batik business.

[12] She later stated that during her divorce from Mustari and her marriage to Subjakto, she relied solely on the income she earned from the film Djandjiku and did not have additional wealth.