Abstract: A method for preparing perovskite nanopowder through a rheological phase reaction at low-temperature that can include: taking hydroxide and metallorganic compound as initial reactants; mixing and stirring the reaction raw materials to form a solid-liquid rheological phase mixture; and controlling the reaction temperature and period, under a low-temperature condition, to prepare perovskite nanopowder in nearly spherical shape and a size of 20-100 nm. This allows for advantages such as controllable product size, low cost, high yield per unit volume, environmental friendliness, high yield per unit volume, and high repeatability. The perovskite nanopowder obtained by this way is nearly spherical, are uniform in size distribution and have controllable granularity. This can be used as the ceramic substrate for electronic components such as high-end chip capacitors and PTC thermistors, etc., as well as the raw material for manufacturing ceramic 3D printing additives and electronic ceramic ink.