In a screen printing apparatus, a first printing table and a second printing table are alternately driven to move horizontally between a workpiece introducing section and a workpiece printing section by a table driving unit. The table driving unit is constituted so that the first printing table is vertically moved from a first level to a second level during the horizontal movement of the first printing table, and so that the second printing table is maintained at the first level during the horizontal movement of the second printing table, whereby the first printing table can pass by the second printing table without interference therebetween when these tables meet each other. In either of the workpiece introducing section and the workpiece printing section, each of the first and second printing tables is always located at the same first level, and thus an unprocessed workpiece (W) loaded onto each of the first and second tables can be subjected to a screen printing process in the same control manner.