The present technology relates to a solid-state imaging device, manufacturing method of a solid-state imaging device, and an electronic device, which can provide a solid-state imaging device having further improved features such as reduced optical color mixing and the like. Also, an electronic device using the solid-state imaging device thereof is provided. According to a solid-state imaging device having a substrate and multiple photoelectric converters that are formed on the substrate, an insulating film forms an embedded element separating unit. The element separating unit is configured of an insulating film having a fixed charge that is formed so as to coat the inner wall face of a groove portion, within the groove portion which is formed in the depth direction from the light input side of the substrate.