Symbolic regression (SR) is used to guide the design of new oxide perovskite catalysts with improved oxygen evolution reaction (OER) activities. A simple descriptor, *u*/t, where *u* and *t* are the octahedral and tolerance factors, respectively, is identified, which accelerates the discovery of a series of new oxide perovskite catalysts with improved OER activities. Five new oxide perovskites were synthesized and their OER activities characterized. Four of them showed high intrinsic activities.