This experiment was performed to investigate apoptosis during undergoing patho-genesis of Salmonella gallinarum(SG)-infected chicks. 16 days old, 49 chicks was infected with SG (10$^$6/-10$^$8/ CFU/㎖) experimentally, they were autopsied to remove liver, spleen, intestine and lung at 1, 6, 12hr, 1, 2, 4 and 7 day post infection(PI) respectively, for H-E and TUNEL staining. Grossly, white foci in the liver and enlarged spleen were seen on 4 day PI and coppery bronze liver, dark-red discolored intestine, green-yellowish discolored and enlarged spleen was observed on 7 day PI. Histopathologically, multi focal necrosis in the liver, follicle hyperplasia in the spleen and inflammatory cells infiltration in the intestine were shown from 2 day PI and more severely observed on 4 day and 7 day PI. In TUNEL analysis, apoptotic cells reached a maximum at 6hr PI in the liver and intestine and at 12hr PI in the spleen, and then decreased the levels of controls by 7 day PI.