State elections were held in South Australia on 17 September 1977. All 47 seats in the South Australian House of Assembly were up for election. The incumbent Australian Labor Party led by Premier of South Australia Don Dunstan won a fourth term in government, defeating the Liberal Party of Australia led by Leader of the Opposition David Tonkin. Background Parliamentary elections for the lower house of the Parliament of South Australia were held in South Australia in 1977. There was no election for Legislative Council; and as of 2020, this is the most recent South Australian election which has not been for both houses. The Labor Party led by Don Dunstan, which had won the previous three elections in 1970, 1973 and 1975, defeated the Liberal Party of Australia opposition led by David Tonkin. It was the first time that a Labor government in South Australia had been re-elected for a fourth term, and would be the first nine-year-incumbent Labor government. This would be Dunstan's last election before resigning due to ill health in 1979. This was the first election after the end of Playmander seat weighting where one vote one value was introduced. At the previous election some metropolitan seats still saw more than three times the number of voters than in some rural seats, despite most of the Playmander being abolished nearly a decade ago. The redistribution was the reason Dunstan called an early election. The Australian Democrats ran for the first time under a joint New LM-Australian Democrats ticket, winning an average 12.3 percent of the primary vote in the 12 electorates they contested, with former LCL MP Robin Millhouse retaining his seat of Mitcham, which he would hold until 1982. Key dates Issue of writ: 25 August 1977 Close of nominations: 2 September 1977 Polling day: 19 September 1977 Return of writ: On or before 3 October 1977 Results Keith Russack stood as an Independent Liberal, but later joined the Liberal Party; giving the numbers: 27 Labor, 18 Liberal, 1 Country Party, 1 Australian Democrat. A 1979 Norwood by-election was triggered as a result of Dunstan's resignation. Labor retained the seat on a considerably reduced majority. |} Seats changing party representation This table lists changes in party representation at the 1977 election. Members listed in italics did not recontest this election. Keith Russack was the sitting Liberal member for the abolished district of Gouger. He was