An election to all 29 seats on Donegal County Council took place on 20 June 1985 as part of the 1985 Irish local elections.

County Donegal was divided into six local electoral areas (LEAs) to elect councillors for a five-year term of office on the electoral system of proportional representation by means of the single transferable vote (PR-STV).

This term was extended for a further year, to 1991.

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