Laser coloring enhances material surface performance and imparts aesthetic appeal or achieves extinction effects. In this study, the single-factor variable method was employed to conduct laser coloring tests on the surface of TC4 alloy, aiming to determine the coloring behavior of titanium alloys and the energy density thresholds for various colors. Four stable coloring effects were selected for SEM and elemental composition analysis to elucidate the mechanism of laser coloring. The results indicate that the cumulative absorbed energy density of titanium alloy materials dictates the color appearance in laser surface coloring, with the color threshold energy density ranging from 1.25 J/mm² to 20 J/mm². Further investigation reveals that the surface morphology resulting from the interaction between the laser and titanium alloy materials, along with the extent of oxidation and carbonization, are the underlying factors determining the coloring effect.