A method for monitoring condition of a vibronic sensor for determining and/or monitoring at least one process variable of a medium in a containment and having at least one sensor unit having a mechanically oscillatable unit includes: exciting the mechanically oscillatable unit by means of an excitation signal such that mechanical oscillations are executed, and receiving the mechanical oscillations in the form of a received signal, determining a measured value for amplitude and a measured value for frequency of the received signal, comparing the measured values for amplitude and frequency with reference values for amplitude and frequency, and ascertaining a condition indicator from the comparison.