Abstract: Based on the good potential of wet grinding in improving starch properties, this study aimed to explore the effect of wet grinding on the structure and properties of starch-lipid complexes. Corn starch and lauric acid were used as raw materials, and starch-lipid complex was prepared by the two treatment methods of compound before wet grinding (C/WG) and wet grinding before compound (WG/C). X-ray diffraction results showed that Control, CS-WG/C and CS-C/WG samples represented strong V-type crystal characteristic diffraction peaks. Fourier-transform infrared showed that samples had two new absorption peaks at 2 850 cm^-1 and 1 740 cm^-1. Control had the endothermic peak of type I complex at 87-95℃ and type Ⅱ complex at 107-113℃. CS-WG/C and CS-C/WG had an endothermic peak of type Ⅱ complex at 106-122℃. These results confirmed the formation of starch-lipid complexes between corn starch and lauric acid. Meanwhile, with the increase of wet grinding time from 0 min to 10 min, the composite index, the intensity of V-type crystal characteristic diffraction peak, T'_p, T'_c and ΔH' of CS-WG/C and CS-C/WG gradually increased. It suggested that proper wet grinding treatment could promote the formation of starch-lipid complex. In addition, compared with CS-C/WG at the same WG time, CS-WG/C granules showed a higher composite index, V-type crystal characteristic diffraction peak intensity and ΔH'. It was thus clear that WG/C was more beneficial to the formation of more starch-lipid complexes. The formation of starch-lipid complex endowed starch with higher thermal stability and lower digestibility, solubility and swelling power. CS-WG/C-10 had the highest content of resistant starch (36.32%), the lowest solubility (3.9%) and the lowest swelling power (7.8 g/g). This study could provide a theoretical basis for the application of wet grinding treatment in the production of starch lipid complexes.