Ziba Cary Keith (13 July 1842 – 5 April 1909) was a Massachusetts businessman and politician who served in both houses of the Massachusetts Legislature, as the first, third, and seventh Mayor of Brockton, Massachusetts and as a member of the Massachusetts Executive Council.

Keith was born on July 13, 1842[2] in Brockton, Massachusetts when it was known as North Bridgewater, Massachusetts.

[4] Keith was educated in the local schools and at the Pierce Academy in Middleborough, Massachusetts.

[4] Keith married Abbie F. Jackson, daughter of Oliver Jackson, on July 13, 1865.

[2] In December 1881 Keith was elected the first mayor of Brockton, Massachusetts, he was sworn in on the first Monday in January 1882.