Kiai Haji Zainul Arifin (born 2 September 1909 – 2 March 1963) was an Indonesian politician who served as deputy prime minister of Indonesia, 2nd speaker of the DPR, and a leading figure of the Nahdlatul Ulama.

In addition, Zainul Arifin also received a religious education in mosques and Madrasas while also undergoing the traditional martial arts training of Pencak Silat.

[1] After quitting the gemeente, Arifin then chose to work as an elementary school teacher and as an educator for adults Sekolah Pendidikan Rakyat, in the Meester Cornelis Region (Now Jatinegara).

Zainul's expertise in delivering speeches, debating, and preaching in Dutch and English had caught the attention of leaders of the Nahdlatul Ulama, including Wahid Hasyim, Mahfouz Siddiq, Muhammad Ilyas, and Abdullah Ubaid.

[2] During the era of Japanese military occupation, Zainul Arifin became a representative of the NU in the management of the Indonesian Muslim Shura Assembly (Masyumi) and was involved in the creation of the paramilitary group Hezbollah.

Zainul Arifin was tasked with the creation of the tonarigumi, a precursor to the current rukun tetangga, in Jatinegara, and eventually in other villages situated on the island of Java.

Zainul was then charged with representing the Masyumi Party's faction within the Central Indonesian National Committee (KNIP), the precursor to the People's Consultative Assembly (MPR), while continuing to hold the leadership of Hezbollah, which had also been integrated into the armed forces.

The General Election in 1955 had ushered Zainul Arifin to become a member of the Constituent Assembly and deputy Speaker of the DPR until the two institutions were dissolved by presidential decree 5 July 1959.

[2] During the early days of the Guided Democracy era, he then chaired the House Mutual Aid (DPRGR) in an effort to strengthen the Communist Party of Indonesia ("PKI") in parliament.