1966 Arizona House of Representatives election

The 1966 Arizona House of Representatives elections were held on November 8, 1966. Voters elected all 60 members of the Arizona House of Representatives in new multi-member districts to serve a two-year term. The elections coincided with the elections for other offices, including Governor, U.S. House, and State Senate.

Following the landmark Reynolds v. Sims (1964) US Supreme Court decision, every state had to redraw state electoral districts to be approximately equal in population. Before Reynolds, the Arizona House consisted of 80 members each elected from a single district; however, districts could not span more than one county, which resulted in population imbalances between House districts. After the ruling, the Arizona House shifted to multi-member electoral districts that could span across counties.

Primary elections were held on September 13, 1966.

Prior to the elections, the Democrats held a majority of 45 seats over the Republicans' 35 seats.

Following the elections, Republicans flipped control of the chamber and took a majority of 33 Republicans to 27 Democrats. Since the total number of House members decreased from 80 to 60, both parties saw decreases in membership; however, the Democrats' decline was much more precipitous: Democrats lost 18 seats while Republicans only decreased by two members.

As of August 1, 2023, Republicans have maintained uninterrupted control of the Arizona House of Representatives since the 1966 election.

The newly elected members served in the 28th Arizona State Legislature, during which Republican Stan Turley was chosen as Speaker of the Arizona House.