66th Oregon Legislative Assembly

The 66th Oregon Legislative Assembly was the legislative session of the Oregon Legislative Assembly that convened on January 14, 1991, and adjourned June 30, 1991. It was held at the Oregon State Capitol in Salem. Democratic members held majorities over the Republican members in both the Senate (20–10) and the House of Representatives (27–33).

Senate
Jane Cease resigned July 31, 1991 to accept appointment as Administrator of Motor Vehicle Division; Ron Cease was appointed by Multnomah County Commissioners to fill the vacancy on August 22, 1991. Mike Thorne resigned January 17, 1991 to accept his appointment as Director of the Port of Portland; Scott Duff was appointed on February 17, 1991, to fill the vacancy. Larry Hill resigned November 1, 1991, to become a lobbyist; Bill Dwyer was appointed by Lane County Commissioners to the seat on November 26, 1991.

House
Judy Bauman resigned on November 1, 1991, to accept appointment as Administrator of the Community Services Division. Kate Brown was appointed on November 26, 1991, to fill the vacancy. Tom Brian changed parties, from a Democrat to Republican on September 5, 1991. Ronald Cease resigned from House and was appointed to the Senate on August 22, 1991. Avel Gordly was appointed on September 30, 1991, to fill the vacancy. William Dwyer resigned from the House and was appointed to Senate on December 4, 1991. Lee Beyer was appointed December 30, 1991 to fill the vacancy. Bob Pickard changed parties from Republican to Democrat on September 12, 1991. Gail Shibley was appointed on January 16, 1991, to fill the vacancy of Phil Keisling who resigned from the sixty-fifth legislative assembly on January 14, 1991.