The method for monitoring engagement time in daily life includes receiving a first radio frequency signal from a first signal source containing a first identification information of the first signal source; matching the first identification information with pre-defined identification information; storing in-time of the said first radio frequency signal with respect to the first identification information; checking the existence of the first radio frequency signal; storing the out-time when the first radio frequency signal is out of range. The engagement time duration between the in-time and the out-time with respect to the first identification information can be computed.