To provide an organic piezoelectric material having a piezoelectric property and pyroelectricity, especially high in orientation and thermally stable, and an ultrasonic probe using the same.

The organic piezoelectric material contains a compound containing at least one of a repetitive unit represented by a formula (1) with a glass transition temperature not lower than 100°C and not higher than 130°C. In the formula, Q represents a polymer main chain. A1represents an alkylene group and an oxyalkylene group, and A1, A2represent mesogen groups. Y represents a divalent linking group selected from among a urea group, a thiourea group, a urethane group, a thiourethane group, an amide group, a thioamide group, a carbonate group, a sulfonamide group, and a sulfondiamide group. Z represents a group selected from among a heterocyclic group, an aromatic group, and an aliphatic group of a carbon number 1-25.

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