The work aims to prepare the environmentally-friendly thermo-chromic anti-counterfeit ink with extensive application scope. The reversible thermo-chromatic compound was prepared with leuco dye (thermosensitive black), developer (Bisphenol A) and solvent (tetradecyl alcohol), and then the microcapsule was covered through in-situ polymerization. Finally, the microcapsules were added to UV system of binders to prepare the reversible thermo-chromic UV inks and analyze the colorimetric properties of ink. The microcapsule grain size was smaller and the color developing effect was better when the emulsification speed was 16 000 r/min, pH value of 2～3, emulsification temperature of 45 ℃ and emulsification time of 30～40 min. The CIE-Lab colorimetric properties of the reversible thermo-chromatic UV ink samples were analyzed. After the whole heating/cooling circle, the lightness (L*) of the ink was changed back to the original value and the lightness change of the ink was delayed. In the whole process, the lightness values of samples were formed as a closed loop. The reversible thermo-chromic ink prepared in such method characterized by convenient detection and significant color change effect, etc. has broad application prospects.