Rayleigh-Taylor (RT) instability occurs when a denser fluid is positioned above a less dense one, leading to instability under the influence of gravity[1]. This phenomenon arises because the gravitational potential energy is at a saddle point rather than a stable equilibrium, making the system susceptible to small disturbances. Recently, Mora observed RT instability in soft solids, such as a hydrogel in a cylindrical container, where the hydrogel moves downward due to its higher density compared to air, which rises[2]. The system stabilizes when the gravitational potential energy is balanced by the elastic potential energy of the hydrogel. However, these studies were conducted under normal gravity and did not explore the effects of hypergravity on hydrogel instability. Here, we experimentally show the phenomenon of hypergravitational Rayleigh–Taylor instability (HRTI) in solids using centrifugal acceleration[3]. We observed that a hydrogel plate in a centrifuge develops surface deformation with a pattern when the centrifugal acceleration goes beyond a certain threshold. The mechanism is that hypergravity increases gravitational potential energy, which overcomes the elastic energy stored in the hydrogel plate. We developed a finite deformation model to predict the start of HRTI and post-buckling patterns. This model shows that a dimensionless critical hypergravity exists for a wide range of geometric sizes, mass densities, elastic moduli and gravitational accelerations. We also observed that hydrogels with different boundary constraints show two types of instability under hypergravity. These two types are HRTI and Fringe instability, and we identified their competitive and transformative mechanisms. Our findings suggest that hypergravity may provide a new way to adjust the Rayleigh-Taylor instability of solids by changing gravitational potential. The results may serve as a reference for explaining natural instabilities related to hypergravity, supporting healthcare in hypergravity environments, and enabling industrial production of (micro)patterns.