Abstract: The NMR as the main method combining with MRI were used to study the mechanism on the effect of the quality of duck yolk with salt. The experiment determined the changes of the sample texture,soluble protein content,and oil exudation under different salt content. At the same time,the correlation of relaxation behavior between texture properties and oil exudation were analyzed respectively.The result showed that: firstly,salt had a significant effect on yolk's relaxation behaviors and texture properties.Both of them showed regular changes with the increase of salt content.Secondly,with the increase of salt content the content of soluble protein increased first and then decreased,the oil exudation decreased and then increased.Meanwhile,the relaxation behavior was significantly correlated with the texture properties and oil exudation.It showed that salt could change the distribution and migration of hydrogen in duck yolk,causing the changes of the content of soluble protein and oil exudation and further affecting the quality of duck yolk.