The chaperone property of sodium caseinate has not been applied to prevent the thermal aggregation of egg white proteins. The effect of sodium caseinate on thermal aggregation of egg white proteins was analyzed via measuring the turbidity, soluble protein content of supernatant, particle size and molecular weight distribution. When the concentration of sodium caseinate was 2mg/mL,the thermal aggregation (90℃, 30min) of egg white proteins solution (5mg/mL) could be suppressed. And with the increasing of the addition of sodium caseinate (2-3mg/mL), the inhibitory effect was enhanced.Due to the low solubility of sodium caseinate, the inhibitory effect of the aggregation was not significant changed at higher concentration of sodium caseinate (4-5mg/mL). The results of SDS-PAGE illustrated that the inhibitory effect of sodium caseinate on the thermal aggregation of ovalbumin and ovaltransferrin determined its effect on preventing thermal aggregation the egg white proteins.With the increase of the addition of sodium caseinate, the insoluble aggregates of egg white proteins was gradually changed to soluble aggregates, and the large and dense aggregates were transformed to small and loose. The results indicated that sodium caseinate could prevent the thermal aggregation of egg white proteins.