A piezoelectric drive device 2 includes cases 4 and 5 and a drive device body 6. The drive device body 6 includes a displacement expanding plate 10, a biasing unit 15 and piezoelectric elements 17 and 18. The displacement expanding plate includes a body 110 biased to rotate by the biasing unit 15, and a displacement expanding portion 120 expanding a displacement when the piezoelectric elements 17 and 18 are expanded to be displaced relative to the body in a direction perpendicular to an expanding direction of the piezoelectric elements. In a state where no voltage is applied to the piezoelectric element, a first driven object 31 is moved by the body that is biased by the biasing unit. When a voltage is applied to the piezoelectric element 17, a second driven object 32 is moved by the displacement portion 120. When the voltage is further applied to the piezoelectric element 17 in a state where the second driven object 32 abuts on an object such that the displacement of the displacement expanding portion is expanded, the body 110 and the first driven object 31 are moved against a biasing force of the biasing unit in a direction opposite to a biasing direction of the biasing unit.