Abstract: Disclosed is a piezoelectric body having both broad band property and improved piezoelectricity, which can be suitably used for a sensor, an actuator, an ultrasound transducer and the like. The piezoelectric body is featured in that (a) it comprises a laminate structure which is represented by the following general formula, General formula G2MX4 wherein G represents an organic onium, M represents an element of Group IV or a transition metal, and X represents Cl, Br or I, the organic onium G and an inorganic phase MX4 being alternately superposed on each other in the form of layers; or in that (b) it comprises a composite of a graphene structure and a perovskite structure, the graphene structure being composed of aggregate particles with an average particle size of not more than 200 nm.