| Election Name: | 1970 Singaporean by-elections |
| Country: | Singapore |
| Flag Year: | 1970 |
| Flag Image: | Flag of Singapore.svg |
| Type: | legislative |
| Previous Election: | 1967 Singaporean by-elections |
| Previous Year: | 1967 |
| Next Election: | 1977 Singaporean by-elections |
| Next Year: | 1977 |
| Seats For Election: | 5 seats to the Parliament of Singapore |
| Election Date: | 18 April 1970 |
| Registered: | 25,310 |
| Turnout: | 21,550 (85.14%) |
| Leader1: | Lee Kuan Yew |
| Party1: | People's Action Party |
| Seats1: | 5 |
| Popular Vote1: | 14,545 |
| Percentage1: | 69.93% |
| Party2: | United National Front (Singapore) |
| Seats2: | 0 |
| Popular Vote2: | 6,255 |
| Percentage2: | 30.07% |
| MPs | |
| Before Party: | PAP |
| Posttitle: | Elected MPs |
| After Party: | PAP |
The by-elections were held in April, for five seats in the Parliament of Singapore, after the resignation of Members of Parliament of the People's Action Party (PAP). The end result saw PAP winning every of the seats, three seats without a contest, and the remaining two via contest.
On 30 March 1970, five members from the People's Action Party were simultaneously resigned from the government per the party's renewal process, namely Chan Choy Siong, Lim Soo Peng, Lim Cheng Lock, Lee Teck Lim, and Buang bin Omar Jumid. The by-elections were then adjourned on 18 April.
Similar to the 1968 general election, no opposition parties stood except a newly formed United National Front formed from remnants of the now-defunct Singapore Alliance; it only contested the two vacant seats of Kampong Kapor and Ulu Pandan; this left the other three seats, Delta, Havelock and Whampoa, being uncontested during nomination day on 8 April.
Previously, prior to the 1968 election, there were mass resignations by each of the 11 (out of 13) members of Barisan Sosialis in the parliament over the course of the 1966 year, who opted to protest and "struggle for democracy" on the streets, had effectively removed all opposition from the parliament. It was only the second time since Independence where a resignation occurred by the governing PAP, after Joo Chiat MP Fong Kim Heng resigned on medical grounds on 18 October 1966.