Whey protein concentrate (WPC) fibril was made at pH value of 2.0 and 90℃. The investigation focused on the impact of adding CaCl2 on the aggregation of WPC spontaneous, homogeneous nuclei induced WPC and secondary nuclei induced WPC. As adding CaCl2, the properties of the hardness, viscosity and amount of WPC fibril aggregates with formation spontaneous or induced homogeneous/secondary nuclei were all increased, especially for two nuclei induced whey concentrate proteins. Adding CaCl2, the hardness was increased by 1.661 (homogeneous nuclei induced WPC) and 1.821 (secondary nuclei induced WPC) times than that of whey protein concentrate spontaneous, and the viscosity was increased by 2.261 (homogeneous nuclei induced WPC) and 2.479 (secondary nuclei induced WPC) times. The micro morphology using TEM of WPC aggregates was changed from long and semi-flexible fibrils into curly and cluster polymers when mixed CaCl2. And the fluorescence intensity was all decreased by adding CaCl2. It was speculated that because the Th T dye was unable to fully bind with the assembled fibrils. For the two ways of forming fibrils: spontaneous or nuclei induced WPC, there were different results that the aggregation ability of nuclei-induced WPC was even greater than that of spontaneous WPC fibril formation as adding CaCl2.