Abstract: To explore the influence of CaCl₂ on aggregation and structural characteristics of wheat flour gluten at the molecular level, wheat flour was used as the raw material. The effects of CaCl₂ addition on the aggregation characteristics of wheat gluten, the textural characteristics of wheat dough, the extractability and secondary structure of dough gluten were studied. Firstly, the influence of different CaCl₂ additions on gluten aggregation characteristics of wheat flour was analyzed by Gluten Peak Tester. The results showed that the maximum peak time of flour decreased significantly (from 75.67s to 30s), and the maximum torque increased significantly with the increase of CaCl₂ additions (from 50 GPU to 74.67 GPU). Secondly, the texture analyzer was used to analyze the influence of different CaCl₂ additions on the textural characteristics of wheat dough. The results showed that the hardness, springiness and chewiness of dough decreased significantly with the increase of CaCl₂ additions. The resilience did not change significantly with the increase of CaCl₂ additions, adhesion increased first and then decreased and then to be stable. Thirdly, the influence of different CaCl₂ additions on gluten extractability of wheat dough was analyzed by fluorescence spectrophotometer. The results showed that the fluorescence intensity of gluten protein decreased as CaCl₂ additions decreased (0.2% and 0.4%), indicating that wheat gluten extractability decreased significantly (P<0.05). With the further increase of CaCl₂ additions (0.8%-3.2%), the fluorescence intensity of gluten protein did not change significantly, indicating that wheat gluten extractability did not change significantly. Finally, the influence of different CaCl₂ additions on the secondary structure of dough gluten was determined by fourier transform infrared spectroscopy. The results showed that the peak positions and trends of FTIR spectra of gluten proteins with different CaCl₂ additions were basically the same, indicating that the addition of CaCl₂ could not change the specific groups of gluten, but changed the content of secondary structure of gluten. The addition of CaCl₂ significantly decreased the content of β-sheet, increased the content of random coil and β-turn, but did not significantly change the content of α-helix. Overall, the addition of CaCl₂ accelerated the formation of gluten, shortened the aggregation time of gluten, weakened the textural characteristics of dough, and reduced the stability of gluten structure, which reduced the quality of wheat product. Furthermore, these results also provided a theoretical guidance for the flour product processing industry.