The invention discloses a date-adjustable seal mold core. The date-adjustable seal mold core comprises a crankshaft, a year mold core, a moth mold core and a date mold core; the crankshaft is a three-section step type crankshaft; the year mold core, the month mold core and the date mold core are respectively mounted on three sections of the crankshaft; the year mold core includes four cylindrical bodies; the four cylindrical bodies are rotationally connected to the first section of the crankshaft in sequence; the month mold core and the date month core respectively consist of two cylindrical bodies; the cylindrical bodies have the same structures with the cylindrical bodies of the year mold core; the two cylindrical bodies of the month mold core are rotationally connected to the second section of the crankshaft in sequence; and the two cylindrical bodies of the date mold core are rotationally connected to the third section of the crankshaft in sequence. The date-adjustable seal mold core is reasonable in structure setting, convenient for adjustment and less in occupied space.