Rosin pre-treatment was studied to improve the quality of digital textile printing. Silk and cotton media were tested with reactive and pigment inks. The K/S value of cotton printed with reactive ink was decreased by rosin treatment. The K/S values of cotton and silk printed with pigment inks were increased by rosin treatment, making rosin-treated samples more effective in obtaining dark color during pigment ink printing. MIU, MMD, and SMD values, closely related to surface roughness and printing quality, were lowered by rosin treatment. B and 2HB values increased with increasing concentration of rosin used during treatment. Line printing tests showed decreased line blurriness of rosin-treated silk and a sharper line was printing.