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 12 and multiple photoelectric converters 40 that are formed on the substrate 12, an insulating film 21 forms an embedded element separating unit 19. The element separating unit 19 is configured of an insulating film 20 having a fixed charge that is formed so as to coat the inner wall face of a groove portion 30, within the groove portion 30 which is formed in the depth direction from the light input side of the substrate 12.