To quickly fill a bag with medicine containers without damaging the containers, a machine for filling a bag with medicine containers includes: a bag positioning member (4) for positioning and opening a bag (13); a first moving member (37) that reciprocates between a supply position inside the bag (13) and a waiting position outside the bag (13), the first moving member including a bottom surface portion for supporting medicine containers; a second moving member that reciprocates relative to the bag (13) and includes a guide surface (47) guiding medicine containers (11) to the bottom surface portion; and a drive-control means (59) that moves the first moving member (37) from the supply position to the waiting position while maintaining the second moving member (38) in a fixed position relative to the bag (13), thereby causing medicine containers (11) guided by the guide surface (47) to the bottom surface portion to remain in the bag (13).