It has remained a great challenge to synthesize a reversible adhesives that can work well on both dry and wet surfaces for a wide range of roughness. Inspired by the reversible adhesion of biological systems, we show how Ga can be used as synthetic reversible adhesive. Ga adhesion is enabled by the phase change ability of Ga near room temperature (30℃) as depicted in Figure (a). The reversible adhesion is achieved by switching between the liquid and solid phases, and can adhere to even rough and wet surfaces. The advantages of Ga adhesion over other synthetic systems is that it requires low detachment force and therefore exhibits a high maximum-minimum adhesion ratio. While adhesives with high ratios do exist (e.g., 35, 40, 204), they are generally only effective on smooth and dry surfaces. Furthermore, the adhesive properties of Ga were characterized through experiments that measured the adhesion of Ga-coated polydimethylsiloxane (PDMS) posts. Under dry conditions, Ga exhibited a high maximum-minimum adhesion ratio (33–113) across a range of materials with smooth surfaces. The method also worked well under wet conditions (ratio: 18, Figure b (i)) and on rough surfaces (ratio: 178, Figure b (ii)). Thus, we demonstrated one of the potential uses of Ga adhesive by performing pick-and-place operations on non-planar objects. We believe Ga adhesion can be implemented in broad adhesive applications including transfer printing, reconfigurable and climbing robots, electronic packaging and biomedicine.