A potassium niobate deposited body includes an R-plane sapphire substrate, a buffer layer composed of a metal oxide and formed above the R-plane sapphire substrate, a lead zirconate titanate niobate layer formed above the buffer layer, a potassium niobate layer or a potassium niobate solid solution layer formed above the lead zirconate titanate niobate layer, an electrode layer formed above the potassium niobate layer or the potassium niobate solid solution layer, and another substrate formed above the electrode layer.