The present invention is to provide a photoelectric conversion element that exhibits excellent external quantum efficiency and responsiveness to light at all wavelengths in a red wavelength range, a green wavelength range, and a blue wavelength range, an imaging element, an optical sensor, and a compound. The photoelectric conversion element includes, in the following order, a conductive film, a photoelectric conversion film, and a transparent conductive film, in which the photoelectric conversion film contains a compound represented by Formula (1).