A formula of a preform body of high-whiteness under-glaze colorful low-temperature ceramic comprises following components by weight: 31 of dolomite, 7 of kaolin, 8 of feldspar, 16 of smolmitza, 18 of sericite, 10 of quartz, 5 of cobalt oxide and 5 of magnesium oxide. A formula of a glaze comprises following components by weight: 39 of feldspar, 6 of spodumene, 10 of limestone, 10 of SrCO3, 21 of quartz, 5 of kaolin, 6 of talcum and 3 of BaCO3. The whiteness and the lead and cadmium dissolving-out amounts of the high-whiteness ceramic reach international advanced levels. Heat stability can reach a degree that no cracking is generated after heat exchange at 180-20 DEG C. The sintering temperature is reduced by 320 DEG C, thus saving a large amount of fuel oil. Under-glaze pictures are bright in color and are vivid, thus improving largely the product grade. The high-whiteness ceramic is sintered by utilization of an oxidizing atmosphere, and therefore the whiteness is high, the rate of finished products is increased by 20%, and industrial production can be achieved.