This study was designed to determine the vibroactivity parameters of a hermetic harmonic drive. A specially-prepared test bench was used to measure the normal velocity of vibrations and acoustic pressure generated by the unit. Piezoelectric sensors were applied to measure the characteristic values on the body of the prototype. In selected sections of drive, we determined the effective values of acceleration ae and frequency f. For the same points, the effective values of vibration velocity Vc were determined for the corresponding frequencies. The findings presented in this paper enable the assessment of a toothed gear in terms of the quality of its workmanship and wear-related deterioration, which are very important due to the characteristic work of this special drive.