The present technology relates to an imaging element, an imaging device, and a manufacturing apparatus and a method that facilitate electric charge transfer. An imaging element of the present technology includes a vertical transistor that has a potential with a gradient in at least part of a charge transfer channel that transfers electric charge of a photoelectric conversion unit. Also, an imaging device of the present technology includes: an imaging element including a vertical transistor that has a potential with a gradient in at least part of a charge transfer channel that transfers electric charge of a photoelectric conversion unit; and an image processing unit that performs image processing on captured image data obtained by the imaging element. Further, a manufacturing apparatus of the present technology includes a vertical transistor manufacturing unit that manufactures a vertical transistor having a potential with a gradient in at least part of a charge transfer channel that transfers electric charge of a photoelectric conversion unit. The present technology can be applied to imaging elements, imaging devices, and manufacturing apparatuses and methods, for example.