PURPOSE: To eliminate any empty bag by supplementing a product to an empty attachment part when the empty attachment part is generated caused by mis- supply in a packing device for packing small articles like candies, gums, chocolates, crakers, cookies and fishing weights.

CONSTITUTION: The presence or absence of an article to be packed is detected on an attachment 31 of a chain conveyor 3 by a photoelectric sensor 61 provided on a conveying process B, and the signal is input into a computer 6. Only when the article to be packed is not placed on the attachment 31, a product supplement device 2 is operated by the output from the computer. The article to be packed, in a through hole 26 of a slide board 22 positioned in the lower end of a magazine 21 in which the article to be packed is previously contained is dropped on the attachment 31 from an input port provided just above the attachment 31 by its own weight by the transfer of the slide board 22 connected to a drive device. Therefore, the articles to be packed are loaded on the whole of the attachments 31 to be moved to the packing process, so that the generation of the empty bag can be eliminated.