The earliest settlement in Sungai Siput was situated at Pelang, about 2 kilometres from the current town. The settlement was populated by villagers of Minangkabau origins who had earlier settled in Sayong. The settlers were from the family of Malik and the son Tuyub, which family tomb is still visible from the roadside situated in the estate in front of the Rimba Panjang new village. One of the descendants was the late Imam Jusuh, one of the first imams of the Alghufraniah Sungai Siput Mosque and the town councillor. Sister Enson was a well-known traditional healer. One of the surviving siblings is Associate Professor Suhaimi Bin Saidin, a lecturer at Universiti Sultan Azlan Shah in Kuala Kangsar. With the arrival of British planters and tin miners in the early 1850s the focus of activity moved to the present Sungai Siput town.

Sungai Siput is notable for the incident that triggered the start of the Malayan Emergency. The Malayan colonial administration declared a state of emergency on 16 June 1948 after members of the Communist Party of Malaya killed three European plantation managers at a plantation office twenty miles east of Sungai Siput town. The CPM was subsequently banned in July. Many Singaporean historians and anti-communists allege that Chin Peng ordered the killings. Chin Peng claims he had no prior knowledge. In fact, he says he was so unprepared for the start of hostility that he barely escaped arrest, losing his passport in the process, and lost touch with the party for a couple of days.^[1]

Li Weilun, an Esperanto professor at the Beijing Language and Culture University, was born in Sungai Siput in 1936.^[2]

Sungai Siput is governed by Pejabat Daerah Dan Tanah Sungai Siput. In 2010, Sungai Siput had an estimated population density of 49,000 inhabitants. The district's population in 2010 was Malay & other indigenous (Bumiputera) 15,745 (33.1%), Chinese 18,255 (38.4%), Indians 13,439 (28.3%) and other groups 113.^[3]

The Sungai Siput parliamentary seat has consistently voted for Alliance and later Barisan Nasional candidates since independence. However, in the 2008 Malaysian general election was won Dr Jeyakumar Devaraj, a Parti Sosialis Malaysia member who contested under the People's Justice Party (PKR) ticket in the Pakatan Rakyat coalition. Dr Michael Jeyakumar Devaraj defeated the previous incumbent, Dato Seri Samy Vellu, who had held the seat since 1974. The seat was successfully defended by Kesavan Subramaniam (PKR) in the 2018 Malaysian general election. As of 2022, there were 72,452 voters in Sungai Siput. Most of the voters in Sungai Siput are Chinese, followed by Malays, Indians and others.

Mahatma Gandhi Kalasalai Tamil School is the biggest Tamil school in the state with over 1,000 students. The school's construction was commissioned by Tun V. T. Sambanthan in 1954 and was officially opened by Vijaya Lakshmi Pandit, former Indian Prime Minister Jawaharlal Nehru's sister.^{[citation needed]}

• Tamil population by cities

4°49′12″N 101°4′12″E / 4.82000°N 101.07000°E / 4.82000; 101.07000