An apparatus and a method for monitoring a bio-signal measuring condition are disclosed. The apparatus includes a bio-signal receiver configured to receive a bio-signal that is measured from a user, and a processor configured to extract any one or any combination of a waveform feature, a period feature, and an amplitude feature, from the received bio-signal, determine whether the extracted any one or any combination of the waveform feature, the period feature, and the amplitude feature are normal, using at least one predetermined determination reference corresponding to the extracted any one or any combination of the waveform feature, the period feature, and the amplitude features, and monitor a measuring condition of the received bio-signal, based on whether the extracted any one or any combination of the waveform feature, the period feature, and the amplitude feature are determined to be normal.