The deformation transfer from the loaded material to the piezoceramic sensor bounded on the surface of structures is investigated. The strain transfer factor, k , is proposed for the characterization of the deformation transfer from the material measured to the sensor. A three layer model, which consists of the sensor, the adhesive and the material measured, is used for modelling of the deformation within the structure/sensor system. Using a shear lag stress analysis method, the strain field within the three layer structure is analyzed. The closed form expression for the strain transfer factor is derived by using the strain field obtained. The influences of the thickness and the elastic modulus of the sensor and the adhesive on the k are predicted and illustrated.