Provided are an optical filter having excellent light fastness and moisture resistance and having excellent detection accuracy, a structure, and an optical sensor. An optical filter 10a includes a near infrared transmitting filter 1 and a dielectric multi-layer film 2. In this optical filter, the dielectric multi-layer film 2 and the near infrared transmitting filter 1 are in contact with each other, or an organic layer 3 is provided between the dielectric multi-layer film 2 and the near infrared transmitting filter 3. In the optical filter, at least two wavelengths at which a transmittance in a wavelength range of 600 nm or longer and shorter than 1050 nm is 50% are present, and in a case where a wavelength on a shortest wavelength side is represented by λ1 and a wavelength on a longest wavelength side is represented by λ2 among the wavelengths at which the transmittance is 50%, predetermined conditions are satisfied.