Ti3Al compounds have potential applications in the aerospace field because of their exceptional mechanical performance at high temperatures, while poor processability becomes the main bottleneck of their applications. This study aims to analyze the tool wear characteristics of the tool flank and their impact on cutting forces during ultrasonic vibration-assisted milling (UVAM) of Ti3Al compounds, with the goal of optimizing cutting parameters and improving machining efficiency. Based on the oblique cutting theory, a milling force model that accounts for tool flank wear was developed. Ti3Al workpieces were subjected to side-milling and up-milling on an UVAM platform. The wear characteristics of the tool and the variations in cutting force with respect to different milling lengths, cutting parameters, and ultrasonic amplitudes were analyzed. The results show that the wear condition of tool flank has a direct impact on cutting force. The cutting force prediction model that incorporates tool wear demonstrated higher accuracy, with average relative deviations of 9.13 % and 13.38 % for the Fx and Fy components, respectively. Adhesive wear is the primary type of tool wear throughout the machining process. Compared to conventional milling (CM), UVAM significantly reduces tool wear, with the wear rate decreasing by approximately 38.4 %, but a too-large amplitude causes additional stress and damage to the tool surface. The research demonstrates that reasonably controlling the cutting parameters and ultrasonic amplitude is effective to slow down the tool wear and lower the cutting force, resulting in good surface quality and machining efficiency.