This work has been designed to investigate possible effects of Nigella sativa supplementation on the mice experimentally infected with Salmonella Typhirnudutn using the electron microscope. The mice that took diet with Nigella sativa and experimentally infected with Salmonella Typhimurium showed survival rate of 96% compared with the group that had diet without Nigella sativa. Also, electron microscopical observation revealed that mice treated group with Nigella sativa showed few changes in the liver as slight mitochondria swelling and less cytoplasmic and nuclear alteration, while, those of non-treated group showed changes included swelling of mitochondria, proliferation of rough endoplamic reticulum, cytoplasmic condensation and nudear degeneration, dilatation of sinusoid and intracellular space.