The gaiwan is important in tea tasting due to its open and glazed surfaces, the former allowing the tea to be viewed while brewing, and the latter not altering the taste and flavors of the tea. The Gaiwan consists of a saucer, bowl, and lid. The lid allows the tea to be infused right in the bowl and either be drunk right from the bowl (traditionally using the lid to block the leaves for ease of consumption), or decanted into another container.

Gaiwan is the preferred method for brewing green and white teas as the Gaiwan's porcelain absorbs the heat and do not damage the tea. It is not suitable for Oolong and black teas as the large lid will let the heat out too quickly during the steeping process.