PURPOSE : An encryption method for a health care medical sensor and apparatus thereof are provided to transmit encrypted hospital medical data to a base system by encrypting the signal of the hospital medical data in low power.CONSTITUTION : An encryption unit(104) encrypts the sensing signal of sensors(1021~102N). An encryption key creation unit(106) creates an encryption key in low power. The encryption key creation unit provides the encryption key to the encryption unit. A communication module(108) transmits the encrypted sensing signal to a hospital server(110). The encryption key creation unit includes a linear feedback movement register, a non-linear feedback movement register, a memory, and a non-linear function processing module.COPYRIGHT KIPO 2012