A piezoelectric pump comprising: a vibrating device comprising: a flat-plate-shaped piezoelectric part; a first bonding part bonded to a principal surface of the piezoelectric part, the first bonding part applying a residual stress in a compressive direction to a bonding surface of the piezoelectric part; a second bonding part bonded to the first bonding part such that the second bonding part faces the piezoelectric part, the second bonding part receiving a residual stress in the compressive direction from the first bonding part; and a pump body including a fluid passage provided therein, the fluid passage extending from a pump chamber open hole of a pump chamber and communicating with the outside through a fluid passage open hole, wherein the first bonding part is a vibrating plate which defines a portion of a wall surface of the pump chamber, wherein a deformation of the vibrating plate is periodically repeated to present a state of the vibrating plate being bent so as to be downwardly convex and a state of the vibrating plate being substantially flat and a state of the vibrating plate being bent so as to be upwardly convex and a state of the vibrating plate being substantially flat again, wherein a coefficient of linear expansion of the vibrating plate is higher than a coefficient of linear expansion of the second bonding part and a coefficient of linear expansion of the piezoelectric element. a vibrating device comprising: a flat-plate-shaped piezoelectric part; a first bonding part bonded to a principal surface of the piezoelectric part, the first bonding part applying a residual stress in a compressive direction to a bonding surface of the piezoelectric part; a second bonding part bonded to the first bonding part such that the second bonding part faces the piezoelectric part, the second bonding part receiving a residual stress in the compressive direction from the first bonding part; and a pump body including a fluid passage provided therein, the fluid passage extending from a pump chamber open hole of a pump chamber and communicating with the outside through a fluid passage open hole, wherein the first bonding part is a vibrating plate which defines a portion of a wall surface of the pump chamber, a flat-plate-shaped piezoelectric part; a first bonding part bonded to a principal surface of the piezoelectric part, the first bonding part applying a residual stress in a compressive direction to a bonding surface of the piezoelectric part; a second bonding part bonded to the first bonding part such that the second bonding part faces the piezoelectric part, the second bonding part receiving a residual stress in the compressive direction from the first bonding part; and a pump body including a fluid passage provided therein, the fluid passage extending from a pump chamber open hole of a pump chamber and communicating with the outside through a fluid passage open hole, wherein the first bonding part is a vibrating plate which defines a portion of a wall surface of the pump chamber, wherein a deformation of the vibrating plate is periodically repeated to present a state of the vibrating plate being bent so as to be downwardly convex and a state of the vibrating plate being substantially flat and a state of the vibrating plate being bent so as to be upwardly convex and a state of the vibrating plate being substantially flat again, wherein a coefficient of linear expansion of the vibrating plate is higher than a coefficient of linear expansion of the second bonding part and a coefficient of linear expansion of the piezoelectric element.