The invention discloses a core nozzle for thin-strip continuous casting and a manufacturing method thereof. The core nozzle comprises the components of ZrO2, MgAl2O4 and C. The manufacturing method comprises the following steps of uniformly mixing various components according to a certain ratio; then putting the mixture into a mold; standing at normal temperature for a period of time; then pressing and forming by an isostatic pressing process; sintering for a certain time at a certain temperature, and finally machining to obtain the finished product. The prepared core nozzle is used for double-roller thin-strip continuous casting and is good in molten steel erosion resistance, can be continuously soaked in molten steel at 1600 DEG C for more than 8 hours and does not react with molten steel to form a large amount of slag, the number of the thin-strip continuous casting continuous casting furnace can be remarkably increased to more than 7 or above, therefore the continuous casting production continuity of the thin strip is improved, the production cost is reduced, and the strip steel product of the thin-strip continuous casting has more cost advantages.