The pressure effects on LiSbO3have been investigated via first-principles simulation. Multiple pressure-induced reconstructive phase transitions between nonperovskite and perovskite states are revealed, i.e., undergoing Pncn-to-R3c-to-P6322-to-Sb:A Pnma-to-P63/mphase transitions with increasing pressure. New nonperovskite P6322 and P63/mstates, not present on experiment, can form a reversible transformation (belonging to displacive-/quasi-reconstructive transition in nature) with the increase and decrease of pressure, involving indirect softening of two unstable phonon modes via symmetry analysis. The anomalous formation of a novel Sb:A Pnmastate, instead of the Sb:B Pnmastate as we commonly expected, is also revealed and explicated by the change of Li–O and Sb–O bonds as well as the limit of the typical tolerance factors. The dielectric response and anomalous larger band gap under a high pressure are also accompanied by the change of direct-to-indirect band gap. All of these findings stimulate interest in the exploration and experimental confirmation of such novel and diverse nonperovskite and perovskite structures as well as their optical applications.