A health monitoring device is provided and includes a detecting unit for detecting a first electric signal from a human body and a processing unit for performing the following steps: receiving the first electric signal; performing wavelet transform on the first electric signal, to filter frequency bands thereof which include undesired noises, and then perform a reverse wavelet transform to obtain a second electric signal; combining frequency bands of the first electric signal which include primary characteristics and then perform a reverse wavelet transform on the combined frequency bands to obtain a fourth electric signal; and comparing the fourth electric signal with a plurality of electric signal patterns of a database to determine whether the fourth electric signal is an electric signal for healthiness.