He helped type a copy of the Proclamation of Indonesian Independence, which Sukarno proclaimed to Indonesia on 17 August 1945.

[1][2] He was the husband of Soerastri Karma Trimurti, a journalist and activist in the women's rights and Indonesian independence movements.

He was arrested in 1926 for allegedly helping the Indonesian Communist Party (PKI), and subsequently exiled to Boven Digul from 1927 until 1933.

Upon return from exile, Sayuti met with S. K. Trimurti, and engaged in a variety of movements and activities together and on 19 July 1938, they got married.

In the same year, they founded the newspaper "Koran Pesat" in Semarang, which was published three times a week with a circulation of two thousand copies.

Because the income was small, the couple were forced to carry out other jobs for the newspaper including editorial, printing, sales distribution and subscriptions.

Sayuti Melik was a member of the 'Menteng 31' group, which played a role in the kidnapping of Sukarno and Hatta on 16 August 1945.

The Declaration of Independence was composed by Sukarno, Hatta and Achmad Subardjo at the home of Japanese Rear Admiral Maeda.

Amidst the tense atmosphere, Melik put forward the idea of Sukarno and Hatta signing the Declaration of Independence on behalf of Indonesia.

After they consented, Sayuti immediately typed up a revised version of the declaration stating it was made on behalf of Indonesia rather than saying Sukarno and Hatta were representatives of the Indonesian people.