Multi-component droplets consist of two or more immiscible materials that have a covalent interface with each other. These materials can be classified in the form of compound droplets such as Janus or core-shell structures. Recently, extensive research has been conducted on droplet rebound or acceleration due to the possibility of combining numerous compound droplets with patterned surfaces [1–4]. In this study, the experiment and simulation were used to analyze the effect of the curvature of the surfaces on the Janus droplet rebound and separation efficiency. The dynamic characteristics were investigated for various Weber numbers and viscosity ratios. The Janus droplet attached a high-viscosity component to a low-viscosity component, thereby creating a Janus shape composed of two fluid parts. Here, a collision situation was assumed where the interface between the two fluid parts was perpendicular to the solid surface. The threshold Weber numbers at which separation begins after collision were investigated under several droplet sizes, viscosity ratios, and curvatures of the surface. In addition, a regime map of the separation efficiency of the compound droplet was presented as a function of the viscosity ratio and Weber number. The curve surfaces enabled the liquid to increase the asymmetry of the mass and momentum distributions in synergy with the effect of the anisotropic curvature, thereby causing the substantial reduction in the residence time. The underlying mechanism of altering the residence time on the surfaces was explained based on momentum asymmetry. We believe that the peculiar impact behavior helps with various applications for controlling water repellency, pathogen depositions, and heat transfer performances. ACKNOWLEDGMENTS—This was supported by Korea National University of Transportation in 2023.