Aiming at the problem of poor formability of titanium alloy sheet, the ultrasonic vibration-assisted forming process was studied, the effects of ultrasonic vibration on the mechanical properties of TA2 titanium alloy sheet and the friction coefficient between the contact surfaces were analyzed. On this basis, the ultrasonic vibration-assisted bulging experiment of specimens with different width-to-length ratios was carried out, and the influence of ultrasonic vibration on the bulging force and limit bulging height of TA2 sheet were analyzed. At the same time, based on the grid strain principle, the forming limit diagram of the TA2 sheet was established by measuring the limit strain of the specimens with different width-to-length ratios. The research results show that choosing appropriate process parameters in ultrasonic vibration-assisted forming can not only improve the formability of TA2 sheet, but also reduce the influence of friction on plastic deformation behavior of sheet, thus effectively increasing the forming limit of TA2.