A pulling-up-type continuous casting apparatus comprising: a holding furnace that holds molten metal; a shape defining member disposed above a molten-metal surface of the molten metal held in the holding furnace, the shape defining member being configured to define a cross-sectional shape of a cast-metal article to be cast by cooperating with an actuator as the molten metal passes through an opening formed in the shape defining member; an image pickup unit that takes an image of the molten metal that has passed through the shape defining member; an image analysis unit capable of detecting a fluctuation of the molten metal from the image by comparing a plurality of successively-taken images with one another and determines a solidification interface based on presence/absence of the fluctuation; and a casting control unit configured to change the casting condition when the solidification interface is not within the reference range; wherein the casting control unit is configured to keep the position of the solidification interface within the reference range, and to move the shape defining member vertically by controlling the actuator according to a pulling-up angle (Θ) being determined based on a difference between a height at the center of the solidification interface and a height of the lowest point of the solidification interface, a shape of the opening is designed based on a position of the solidification interface determined by the image analysis unit and the pulling-up angle of the molten metal such that a size of the opening on a top surface of the shape defining member is larger than that on a bottom surface of the shape defining member, and when the molten metal is pulled up in an oblique direction, a degree of submergence of the shape defining member under the molten-metal surface is increased compared to when the molten metal is pulled up in a vertical direction, the degree of submergence being determined based on the position of the determined solidification interface and the pulling-up angle of the molten metal. a holding furnace that holds molten metal; a shape defining member disposed above a molten-metal surface of the molten metal held in the holding furnace, the shape defining member being configured to define a cross-sectional shape of a cast-metal article to be cast by cooperating with an actuator as the molten metal passes through an opening formed in the shape defining member; an image pickup unit that takes an image of the molten metal that has passed through the shape defining member; an image analysis unit capable of detecting a fluctuation of the molten metal from the image by comparing a plurality of successively-taken images with one another and determines a solidification interface based on presence/absence of the fluctuation; and a casting control unit configured to change the casting condition when the solidification interface is not within the reference range; wherein the casting control unit is configured to keep the position of the solidification interface within the reference range, and to move the shape defining member vertically by controlling the actuator according to a pulling-up angle (Θ) being determined based on a difference between a height at the center of the solidification interface and a height of the lowest point of the solidification interface, a shape of the opening is designed based on a position of the solidification interface determined by the image analysis unit and the pulling-up angle of the molten metal such that a size of the opening on a top surface of the shape defining member is larger than that on a bottom surface of the shape defining member, and when the molten metal is pulled up in an oblique direction, a degree of submergence of the shape defining member under the molten-metal surface is increased compared to when the molten metal is pulled up in a vertical direction, the degree of submergence being determined based on the position of the determined solidification interface and the pulling-up angle of the molten metal.