Mechanical properties of skin are a clue for the diagnostic of pressure ulcers (PU) [1]. This project proposes a low- frequency ultrasound (LFU) device to identify the mechanical impedance (MI) of skin in different sites. The device’s goal is to identify the evolution of MI of skin over time and link it with the development of PU. In literature, studies involving LFU and PU focus on debridement through LFU cavitation [2]–[3]. Use of LFU on PU often present reduced pain and faster recovery. Although LFU for PU treatment is widely documented, the use of LFU for diagnosis is unexplored. Thus, a Langevin transducer (LT), with 60kHz of resonance frequency is proposed for PU detection. It is a high efficiency LFU device, based on the piezoelectric effect.