Abstract: The invention is related to a sample holder for measurements of optically detected magnetic resonance, including a bottom plate, a top plate and a middle plate, wherein all the plates are made of a dielectric material. The top plate is provided with at least one top opening, enabling continuous optical access to the studied sample during measurements. The sample is placed in the central opening provided in the middle plate. The non-magnetic conductive strips provided on the surfaces of the bottom plate, the middle plate and the top plate ensure formation of an electrical circuit, which allows coupling of the studied sample with the generated microwave radiation to be achieved once the microwave sources is switched on. The invention also includes a sample holder for measurements of optically detected magnetic resonance, enabling formation of at least one loop of the electrical circuit.