A living body observation system of the invention includes: a living body information acquiring apparatus including a living body information acquiring section for acquiring living body information in a living body, a wireless transmission section for wirelessly transmitting the living body information to outside of the living body, a power source section for supplying driving power for driving the living body information acquiring section and the wireless transmission section, a magnetic field detecting section for detecting a magnetic field from outside and outputting a detection result as an electric signal, and a power supply control section for controlling a supplying state of the driving power supplied from the power source section to the living body information acquiring section and the wireless transmission section based on the electric signal and a magnetic field generating section disposed outside the living body information acquiring apparatus, the magnetic field generating section including a resonant circuit for generating a magnetic field by resonance, and a driving circuit for supplying driving voltage for driving the resonant circuit.
