Disc-milling is used in manufacture, especially for difficult-to-machine material like titanium alloy, because of its strong force and high efficiency. However, the research on cutting mechanism of disc-milling technique is still lack in literature. In the present study, first, disc-milling grooving experiment was carried out to measure milling force and temperature for titanium alloy sample. After machining, surface roughness, surface topography, residual stress, microstructure and microhardness in different milling conditions were analyzed. The results showed that the surface roughness of the center on milling surface was lower than the edge; moreover, the surface roughness decreased with the increase of spindle speed, but increased with the increase of depth of cut and feed speed. The dent and crack were observed on the center and edge of milling surface, respectively. The residual compressive stress was produced on the machined surface and subsurface, and gradually reduced to zero with the increase of depth. The microstructure of lattice tensile deformation was found along feed direction under the effect of milling force, progressing from initial equiaxed structure to long flake lattice. The metallographic structure of plastic deformation zone changed with the temperature, transforming from initial equiaxed microstructure to a lamellar microstructure when the temperature was up to β-phase transition temperature. The combination of mechanical and thermal loads led to an increment in microhardness on the machined surface and subsurface.