The diffraction of a Bleustein‐Gulyaev surface wave by a semi‐infinite conductive surface layer is investigated. It is assumed that the direction of propagation is normal to the edge of the semi‐infinite conductive layer. It appears that, if the dielectric constant ε1of the piezoelectric material is large compared with the dielectric constant ε0of the adjacent half‐space, the relative power flow associated with the reflected surface wave is of the order (ε0/ε1)2. The relative power flow of the transmitted surface wave is of the order ε0/ε1. Hence, if ε0/ε1≪ 1, the largest part of the incident power is converted into a bulk wave. The angular power distribution of the diffracted bulk waves appear to be very asymmetric and concentrated preponderantly in a direction making an angle κ2/(1 + ε1/ε0) with the incident wave, κ being the piezoelectric coupling coefficient.