Hello. The mark says "Da Qing Qianlong Nian Zhi" (made during the Qianlong years of the Great Qing).
This is not a Qianlong reign mark, however. Rather it appears to be a 19th century or late Qing dynasty mark. Red, stamped marks became popular only in the 19th century. This doesn't necessarily mean that the item is fake. Many antiques from the late Qing dynasty and early republic do have Qianlong marks.