James Mercer was a Ghanaian diplomat to Israel during the 1960s and a prominent national lawyer. He was the first chairman of the now-defunct Ghana Airways.

Mercer was born in Sekondi-Takoradi, Ghana. His twin brother was Thomas Mends Kodwo-Mercer and both attended Adisadel College, Cape Coast, as did many of his siblings, children, and grandchildren, a long-standing tradition of his family.

He was a prominent lawyer, working during the government of Kwame Nkrumah and beyond. Mercer was a barrister-at-law at the Sekondi Bar, Chairman of the Ghana/Ivory Coast Border Commission, and first Chairman of the now-defunct Ghana Airways.

From May 24, 1962, to 1963 he was ambassador to Peking.

From July 1, 1964, to February 24, 1966, he was ambassador to Tel Aviv. (Ghana–Israel relations)

He is the father of Andrew Egypa Mercer, a current member of parliament for Sekondi and Esther Mercer. He was also the brother of T. M. Kodwo-Mercer, the first Ghanaian High Commissioner to Britain from 1954 to 1956, and uncle of the former Minister of Trade and Industry, Ekwow Spio-Garbrah.

James Mercer was also the uncle of late Sally Hayfron, the first wife of Robert Mugabe.