A modified ethylenediamine/copper chloride composite with temperature-sensitive continuous multi-color property was prepared by silica sol-gel modification of ethylenediamine copper chloride complex. The ef-fects of the amount of tetraethyl orthosilicate in the sol component on the stability of the composite and the thermochromic properties of the initiator hydrochloric acid were investigated. The thermosensitive col-or change mechanism of the modified ethylenediamine/copper chloride composite was studied. The re-sults show that the water ligand of the composite material is replaced by colorless to yellow color change at 120 ℃. At 160 ℃, the water molecules re-coordinate with the central copper ion, and the nitrogen ligand undergoes proton transfer. Change from yellow to blue. The modified tetraethyl orthosilicate has better stability. With the increase of hydrochloric acid concentration, the coordination probability of chloride ion increases, and the color conversion of modified ethylenediamine/copper chloride composite material is deeper.