The present invention relates to a lamination device for manufacturing electrode cell assemblies by laminating electrodes and separation membranes unwound from an electrode roll and a separation membrane roll, the device comprising: a lamination part in which the electrode cell assemblies are stacked and manufactured; an inspection unit for detecting a defective electrode cell assembly by measuring the thickness of the manufactured electrode cell assemblies; a discharge part for separating the defective electrode cell assembly from the non-defective electrode cell assemblies and discharging the separated defective electrode cell assembly; and a control unit that calculates the point in time at which the defective electrode cell assembly arrives at the discharge part on the basis of data about the distance between the location at which the defective electrode cell assembly is detected and the discharge part, and controls so that the defective electrode cell assembly is separated and discharged upon arriving at the discharge part. Furthermore, the present invention relates to a defective electrode cell assembly discharging method for the lamination device.