The purpose of this study is to observe the macro, micro and ultrastructural changes of the pituitary, adrenal, pancreas and spleen in the experimental primary brain death. The results showed: 1. acinar zymogen granule of pancreas decreased, karyopyknosis of islet cells formed. 2. dilation and blood stasis of spleen sinus happened 3. adrenocortical karyopyknosis formed, mitochondrial crista vanish. 4. Pituitary karyopyknosis and cytolysis developed. 5. there was correlation between the extent of lesions and time after brain death.