This is the cover page of a copied sutra.
It is the 47th volume of the Buddhavatamsaka Mahavaipulya Sūtra written in Chinese characters.
There are two formats for copied sutras: a folded type as in this case, and a rolled type.
In the case of a folded sutra, the cover is frequently decorated with floral patterns. This is an example of the luxuriously decorated folded type.