A special angle beam probe for ultrasonic testing includes at least one ultrasonic vibrator fastened in a beam probe housing on a wedge-shaped support body which may be formed of Plexiglass, using damping means. The ultrasonic beam of the vibrator strikes the surface of the test piece at an incidence angle other than 0.degree., as measured from a perpendicular at the surface of the test piece at the point where the beam strikes. The ultrasonic beam furthermore strikes the test piece surface at an oblique angle between 0.degree. and 360.degree. subtended between a principal beam probe axis and the beam, as seen in the direction perpendicular to the beam probe from above. The novelty of the invention is that the special angle beam probe includes a multiplicity of prefabricated beam probe subassemblies. The ultrasonic vibrator of each subassembly is fastened with a predetermined incidence angle within a first beam probe housing. A second beam probe housing contains the test head subassembly and the test head subassembly can be fastened at least at one predetermined oblique angle within the second housing for forming the overall special angle beam probe. In this way a multiplicity of beam probe subassemblies with the same insonification angle form special angle beam probes with different, predetermined oblique angles, by assembling the subassemblies in second test head housings in different oblique angle relationships.