Method and device for ultrasound testing of welds, particularly for welds of blades on the blisk of a bladed disk.According to the invention, for testing element welds (6) on a body (4), forming a single-piece assembly (2) with these elements, the free end of a poly-articulated robot (12) is fitted with an ultrasound probe (24), fitted with an ultrasonic multi-element array transducer (14); the probe is inserted into the space (10) between two adjacent elements of the assembly; the probe is moved along three-dimensional trajectories along the profile of the element; sectorial electronic scanning is performed in at least two non-parallel testing planes; and ultrasound signals output by the transducer in order to test the welds are processed.