<p>TC4 titanium alloy is a typical difficult-to-machine material. During traditional cutting processes, sawtooth-shaped chips are prone to form, resulting in significant fluctuations in cutting force, severe tool wear, and poor surface quality of the workpiece. In this study, TC4 titanium alloy is selected as the research object, and laser ultrasonic assisted machining technology is employed. Through finite element simulation and experimental investigations, the effects of laser heating and ultrasonic vibration on chip morphology, degree of serration, and serration frequency are systematically examined. The results indicate that laser ultrasonic-assisted machining exhibited the best cutting performance. Simulation results showed that, compared with conventional machining, ultrasonic-assisted machining, and laser-assisted machining, the cutting force was reduced by 49.40%, 36.70%, and 27.90%, respectively; experimental results showed that the degree of chip serration was reduced by 60.96%, 58.17%, and 48.41%, respectively. The back surface of the chip appears smooth without adhesion, and the serrated structure on the free surface nearly disappears. Increasing laser power and ultrasonic amplitude contributes to the suppression of chip serration. The influence of spindle speed on serration shows a trend of “decreasing first and then increasing.” Increasing the cutting depth and feed per tooth exacerbates chip serration. In addition, the surface roughness of the workpiece exhibits a significant positive correlation with the degree of chip serration, suggesting that the quality of the machined surface can be effectively estimated through the evolutionary characteristics of chip formation.</p>