To provide a sheet folding and bonding device which folds a sheet on which a pressure-sensitive adhesive agent is applied so as to prepare a covered post card or the like and in which pressing rollers are enabled to be disposed in a vertical state by surely longitudinally conveying the folded sheet so as to reduce an area in which the device is installed for space saving.

Folded sheets 33A, 33B which are obtained by feeding a sheet 33 on which the pressure-sensitive adhesive agent is applied horizontally relative to a device installation surface and then folding are fallen into a longitudinal conveying zone section 61 in which a longitudinal conveying space 61C is formed vertically relative to the device installation surface by a feeding roller section 62 and a feeding and pressing roller 63. The folded sheets 33A, 33B are sent longitudinally as they are from a conveying belt 64 to the pressing rollers 26A, 26B which are arranged vertically while the folded sheet 33A, 33B are held by the conveying belt 64 and conveying and pressing rollers 65A-65C which are installed in the longitudinal conveying space 61C.