The objective of this invention is to provide a transfer mask that is able to accurately pass micro-balls onto terminal areas on a substrate. A thin plate transfer mask 200 is arranged facing a substrate 100, and possesses a plurality of through-holes 242 for the purpose of passing micro-balls (solder balls) onto a plurality of terminal areas 108 formed on one surface of a substrate 100. Slits 230, 232, 234, 236 formed in the surface of the transfer mask 200 extending in the length direction and the width direction of the transfer mask 200, inside the substrate edge P1 and outside the area in which the plurality of through-holes 242 is formed when it is facing the substrate 100.