Hale was let go by the D-backs at the end of the season after serving as their skipper for two years. He compiled a 148-176 record in Arizona.
Prior to joining the D-backs, Hale was the A's bench coach under manager Bob Melvin from 2012-14. He also served as a third-base coach for the New York Mets from 2010-11.
"We're thrilled to bring Chip back to the organization and to retain the rest of our coaching staff," A's general manager David Forst said in an announcement of the hiring via Twitter on Tuesday.
Hale replaces Ron Washington, who left Oakland to serve as the Atlanta Braves' third-base coach after interviewing for their previous managerial opening.