Abstract: This invention of an apparatus and a method for detecting luminescence from biological systems in response to magnetic fields measures the amount of light emitted when impressing a magnetic field on a living thing, a tissue or cells separated from a living thing to evaluate the effect of magnetic fields on biological systems. The apparatus of this invention consists of a dark box which shields a biological sample from external light, a magnetic field generator which is arranged adjacent to the biological sample to impress a magnetic field on it, and a photodetector which detects the light emitted from the biological sample exposed to the magnetic field from the said magnetic generator.