Provided is a glass film ribbon manufacturing device (1), including: a transverse conveyance unit (4), which is configured to convey a glass film ribbon (G) in a transverse direction; and a cleaving unit (5), which is arranged on a conveyance path of the transverse conveyance unit (4), and is configured to cleave the glass film ribbon (G) along a preset cleaving line extending in a longitudinal direction, the transverse conveyance unit (4) including a wrinkle-smoothing unit (14) configured to smooth a wrinkle generated in the glass film ribbon (G) before the glass film ribbon (G) is cleaved by the cleaving unit (5).