The second election toSouth Glamorgan County Council was held in May 1977.^[1] It was preceded by the1973 election and followed by the1981 election.

There were no boundary changes but the balance of representation in the Penarth wards appears to have changed with the North/Central ward gaining a seat and the West ward losing one.

Conservative andLabour candidates contested the vast majority of seats. In contrast with four years previously there were moreLiberal candidates together with a smaller number ofPlaid Cymru candidates and Independents.

When the authority was established the Conservatives had hoped to win control but failed to do so in 1973. However, they won control at this election, with sweeping gains across Cardiff and the Vale, including some seats which the party had not fully contested at the previous election. Defeated candidates included the leader of the council, Jack Leonard.^{[citation needed]}

Councillor Tresize had sat for the Cadoc Ward at the previous election.

KEY

• indicates sitting councillor for the ward

+ indicates sitting councillor but for different ward

• 1977 Welsh local elections
• South Glamorgan County Council elections

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