| Election Name: | 1977 Cumnock and Doon Valley District Council election |
| Type: | parliamentary |
| Ongoing: | no |
| Previous Election: | 1974 Cumnock and Doon Valley District Council election |
| Previous Year: | 1974 |
| Next Election: | 1980 Cumnock and Doon Valley District Council election |
| Next Year: | 1980 |
| Seats For Election: | All 10 seats to Cumnock and Doon Valley District Council |
| Majority Seats: | 6 |
| Registered: | 33,600 |
| Turnout: | 51.7% |
| Image1: | Lab |
| Party1: | Labour Party (UK) |
| Seats1: | 6 |
| Seat Change1: | 2 |
| Popular Vote1: | 4,613 |
| Percentage1: | 40.1% |
| Swing1: | 4.6 |
| Party2: | Scottish Labour Party (1976) |
| Last Election2: | N/A |
| Seats2: | 2 |
| Seat Change2: | 2 |
| Popular Vote2: | 2,845 |
| Percentage2: | 24.7% |
| Swing2: | 24.7 |
| Image3: | Con |
| Party3: | Scottish Conservative and Unionist Party |
| Seats3: | 1 |
| Popular Vote3: | 954 |
| Percentage3: | 8.3% |
| Swing3: | 12.4 |
| Council Leader | |
| Before Party: | Labour Party (UK) |
| Posttitle: | Council Leader after election |
| After Party: | Labour Party (UK) |
Elections to Cumnock and Doon Valley District Council were held on 3 May 1977, on the same day as the other Scottish local government elections. This was the second election to the district council following the local government reforms in 1974.
The election used the original 10 wards created by the Formation Electoral Arrangements in 1974. Each ward elected one councillor using first-past-the-post voting.[1]
Despite losing two seats, Labour maintained control of the district council, winning six of the 10 seats. The 1977 local elections were the first test for the nationalist Scottish Labour Party (SLP) which had been formed as a breakaway from Labour by South Ayrshire MP Jim Sillars alongside John Robertson and Alex Neil. The SLP achieved its best results in Cumnock and Doon Valley by winning two seats from Labour and taking more than 25% of the popular vote but the party ultimately fared poorly across the country. The Conservatives remained on one seat after losing their seat in Mauchline and gaining Catrine and Sorn. This was the last time the Conservatives would win a seat in the area until the 2017 local elections, 40 years later. The remaining seat was won by an independent candidate.