In this paper, the rheological behavior and thermoplastic deformation of Zr61.88Cu18Ni10.12Al10 bulk metallic glasses (BMGs) in the supercooled liquid region (SCLR) were studied by high temperature compression tests and a processing map was constructed. The results indicated that the flow stress of present alloy in the SCLR is very sensitive to temperature and strain-rate. The flow stress decreases with increasing temperature and decreasing strain-rate. The viscosity coefficient of the present alloy ranges from 1011 Pa.s to 109 Pa.s and decreases with increasing temperature and strain-rate. When the strain-rate is greater than 5 × 10−3 s−1, the Zr61.88Cu18Ni10.12Al10 alloy undergoes a transition from Newtonian fluid to non-Newtonian fluid. The surface profile exhibited a similar shape of the letter ‘N' after high temperature compression in the deeply SCLR. The optimum hot processing region of Zr61.88Cu18Ni10.12Al10 alloy is 688 K–708 K with a low strain-rate and 708 K–723 K with a high strain-rate.