To provide a liquid injection head including a piezoelectric device having a piezoelectric substance layer small in environmental loads and large in strain amounts, and to provide a liquid injection device and the piezoelectric device.

The liquid injection head discharges a liquid through a nozzle opening 21 and includes the piezoelectric device 300 with the piezoelectric substance layer 70 and an electrode disposed on the piezoelectric substance layer. The piezoelectric substance layer is made of a barium titanate complex oxide, the complex oxide having a Perovskite structure containing barium, titanium and copper of not more than 3 mol% relative to the titanium.