The number of senators remained constant at two per county, totaling 28, and the members of the house of representatives also held steady at 80.

The Democrats picked up two seats in the Senate, giving them a 26–2 edge in the upper house, while the Republicans gained three seats in the House, trimming the Democrats majority to 45–35.

The Legislature met for two regular sessions at the State Capitol in Phoenix.

The first Special Session convened April 21, 1965, and adjourned sine die on May 10;[1]: 311  the second convened on May 11, 1965, and adjourned sine die on June 15;[1]: 337  the Third Special session convened on June 16, 1965, and adjourned sine die on July 1;[1]: 375  with the final Special Session, the fourth, convened September 13, 1965 and adjourned sine die on October 9.

[1]: xix The asterisk (*) denotes members of the previous Legislature who continued in office as members of this Legislature.