© 2019 The Chemical Society of Japan. The catalytic function of perovskite oxides has received significant attention because of their structural flexibility and controllable physicochemical properties. In contrast to their catalytic application to gas-phase high-temperature, electrochemical, and photocatalytic reactions, liquid-phase organic reactions with perovskite oxide-based catalysts are still under-explored. Numerous nanosized and porous perovskite oxide catalysts have been synthesized by co-precipitation, sol-gel, solution combustion, and soft/hard templating methods, and these catalyst systems are effective for various types of liquid-phase organic reactions that have been classified into three main groups: (a) cross-coupling reactions, (b) acid/base-catalyzed reactions, and (c) selective oxidation reactions. This review article focuses on the relationships among the structures, the physicochemical properties, and the unique catalytic properties of perovskites in liquid-phase according to groups (a)(c). In addition, the reaction mechanisms, kinetics, spectroscopy, catalyst stability/recyclability, and heterogeneous nature are comprehensively summarized for some catalytic systems.