The invention discloses an automatic installing device of a sealing strip. A rack is included, and an installing support is borne on the rack; a material disk is fixed to the installing support, and asupporting plate is arranged below the material disk; a main support is further arranged on a work table top, and is provided with a first stand column and a second stand column; a cross beam is erected between the top of the first stand column and the top of the second stand column, and is connected with a slider in a sliding manner; a manipulator is fixed to the bottom of the slider; a calibrator is arranged on one side of the first stand column; an assembly line, a material pushing table and a tray are further arranged between the first stand column and the second stand column; a driving cylinder is arranged on one side of the second stand column; a cylinder rod of the driving cylinder is sleeved with the tray, and the tray can reciprocate along with the cylinder rod; a to-be-machinedpulse strip is placed on the assembly line; and when the tray moves to one end of the assembly line along with the cylinder rod, the pulse strip on the assembly line can slide onto the tray.