The invention provides a high-medium single-layer miniature ceramic capacitor substrate material. Raw materials comprise main ingredients and doping agents. Chemical components of the main ingredients are SrTiO3. The doping agents are composed of, by mass, mwt% of Nb2O5, nwt% of SiO2, pwt% of Y2O3, qwt% of CaSnO3 and rwt% of composite oxide additives. The preparation method includes batching, ball-milling, drying, pelleting, forming, glue discharging, reduction atmosphere sintering and oxidation heat treatment. No Pb, Cd or other volatile or heavy metal elements are contained in the formula of the high-medium single-layer miniature ceramic capacitor substrate material, and the high-medium single-layer miniature ceramic capacitor substrate material is an environment-friendly and pollution-free medium ceramic material. The sintering temperature of ceramic is 1340-1400 DEG C, the dielectric constant is high, and a certain energy-saving advantage is achieved; the raw materials are sufficiently supplied at home, price is low, and the high-medium single-layer miniature ceramic capacitor substrate material is suitable for manufacturing high-performance communication components in the modern communication technology.