To provide the manufacturing method of a piezoelectric thin film having excellent crystallinity.

A piezoelectric thin film 1 is deposited in two steps of a first piezoelectric thin film 13 and a second piezoelectric thin film 15. Since the heat treatment is performed after depositing the first piezoelectric thin film 13, crystallinity of the first piezoelectric thin film 13 can be enhanced in comparison with that of the first piezoelectric thin film 13 before the heat treatment. The second piezoelectric thin film 15 which is deposited later is also subjected to crystal growth similar to the first piezoelectric thin film 14 after the heat treatment, and the piezoelectric thin film 1 having the enhanced crystallinity can be obtained on the whole. The film thickness of the first piezoelectric films 13, 14 is ≥ 5 nm and ≤ 100 nm, which is smaller than the film thickness of several μm of the entire piezoelectric thin film 1. The number of defects of the crystal is small in the thin film of the thickness of this value. When the heat treatment temperature is higher than 300°C, the number of defects is small, and the sufficient crystallinity can be obtained. When the heat treatment temperature is ≤ 800°C, peeling of the thin film caused by the difference in the coefficient of thermal expansion from that of a substrate 10 can be reduced.

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