The removal of printing paste from digitally printed fabrics is challenging due to the strong adhesion of thickening agents such as polyacrylamide, which form a gel-like structure on the fabric surface. Conventional washing methods often require multiple cycles, leading to high water and energy consumption. Ultrasonic waves can enhance paste removal through micro cavitation, which disrupts the paste structure and facilitates its detachment from the fibers. This study examines the effectiveness of ultrasonic-assisted washing in removing polyacrylamide-based paste from knitted fabric. Washing trials were conducted at two ultrasonic frequencies (85 and 95%), two temperatures (20 and 40 °C), and without ultrasound (0% frequency) as a control. The remaining paste on the fabric was quantified gravimetrically, while FTIR analysis was performed on washing water to confirm paste transfer. Results indicate that conventional washing (0% frequency, 20 °C) removed 67% of the paste, while ultrasonic washing at 85% frequency improved removal to 71%. Increasing the frequency to 95% further enhanced paste removal to 75.5%. However, raising the temperature to 40 °C at 95% frequency unexpectedly reduced efficiency to 72%, suggesting a change in paste solubility. FTIR spectra confirmed higher paste dissolution into water at higher ultrasonic frequencies. These findings demonstrate that ultrasonic-assisted washing significantly improves paste removal, providing a more efficient and sustainable alternative to conventional methods.