William James Riordan (20 April 1882 – 15 September 1955) was an Australian politician and judge.

In 1916 he became state president of the FNAWU, and in 1917 was appointed to the Queensland Legislative Council for the Labor Party.

In 1925 he moved from president to secretary of the FNAWU, a position he held until 1933 when he was appointed to the Queensland Industrial Court.

He was also involved in the Labor press as director of The Daily Standard and The Worker, which were published in Brisbane.

Jim Riordan's son Bill was elected to the seat of Kennedy on Darby's death in 1936.