The present invention provides a jointed package corner protector, which includes corner plates (1) each of which is formed, in two opposite, upper and lower, ends thereof, with first through holes (11) that are perpendicular to a lengthwise direction of the corner plates (1) and a joint sheath (31) that is formed with second through holes (311) that correspond to the first through holes (11) formed in an upper end of a lower-side corner plate (1) of two corner plates (1) that are arranged adjacent to each other as being respectively set at upper and lower sides and the first through holes (11) formed in a lower end of the upper-side corner plate (1) so that button fasteners (33) may be set to penetrate through corresponding ones of the first through holes (11) and the second through holes (311) to connect the two adjacent corner plates (1) of the upper and lower sides to the joint sheath (31), whereby easy variation of a length of the package corner protector can be achieved accommodate stacked heights of different package specifications of display devices so as to be economic and practical and help improve manufacturing efficiency.