The twentieth election to Cardiganshire County Council took place on 2 April 1955. It was preceded by the 1952 election and followed by the 1958 election.
36 candidates were returned unopposed resulting in only fourteen contests. As was the case three years earlier it was reported that there was little appetite for contests, especially where retiring members sought re-election.
Eight aldermen retired, of whom five sought election. Alderman Simon Davies, Felinfach, announced that he had reluctantly decided to retire from public life at the age of 84 after 33 years as a member of the council. At Devil's Bridge, Llangeitho and Llanwenog the retiring councillors stood down in favour of the retiring aldermen.
The fourteen contests were fought on non-political lines, with three retiring members being defeated. These included Alderman Emlyn Abraham Williams, who was heavily defeated at Aberystwyth.
In addition to the 50 councillors the council consisted of 16 county aldermen. Aldermen were elected by the council, and served a six-year term. Following the 1955 election, there were eight aldermanic vacancies which were filled at the annual meeting. The following retiring aldermen were re-elected:
In addition, the following four new aldermen were elected:
John John was the sole Labour member of the council and the first Labour councillor to be elevated to the aldermanic bench in Cardiganshire.
Two contested by-elections were held to fill aldermanic vacancies.