| Election Name: | 1877 Iowa Senate election |
| Country: | Iowa |
| Flag Image: | Flag of Iowa (variant).svg |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 1875 Iowa Senate election |
| Previous Year: | 1875 |
| Next Election: | 1879 Iowa Senate election |
| Next Year: | 1879 |
| Seats For Election: | 24 out of 50 seats in the Iowa State Senate |
| Majority Seats: | 26 |
| Election Date: | October 9, 1877 |
| Party1: | Republican Party (United States) |
| Last Election1: | 40 |
| Seat Change1: | 2 |
| Seats After1: | 38 |
| Party2: | Democratic Party (United States) |
| Last Election2: | 10 |
| Seat Change2: | 2 |
| Seats After2: | 12 |
In the 1877 Iowa State Senate elections, Iowa voters elected state senators to serve in the seventeenth Iowa General Assembly. Elections were held in 24 of the state senate's 50 districts. State senators serve four-year terms in the Iowa State Senate.
The general election took place on October 9, 1877.[1]
Following the previous election, Republicans had control of the Iowa Senate with 40 seats to Democrats' 10 seats.
To claim control of the chamber from Republicans, the Democrats needed to net 16 Senate seats.
Republicans maintained control of the Iowa State Senate following the 1877 general election with the balance of power shifting to Republicans holding 38 seats and Democrats having 12 seats (a net gain of 2 seats for Democrats).
District boundaries in the Iowa Senate were redrawn before the 1877 general election.