The invention provides a teacup accessory simple in structure and handy. A following technical scheme is used herein: the teacup accessory, comprising a heat-insulating ring and a coaster, wherein the heat-insulating ring and the coaster are of split structure, the heat-insulating ring comprises an outer sleeve and spring steel wrapped in the outer sleeve, the coaster comprises a cup opening, a cup bottom and a telescopic structure in a corrugated shape, the cup opening is greater than the cup bottom in diameter, and the cup opening may suck fixedly onto a plane. By using the scheme, stress produced by deformation of the spring steel enables the spring steel to contract to its minimum inner diameter and surround a cup body; owing to high friction of silicone, no slipping will occur on the cup body; there is no need for a circle of surrounding, appearance is greatly improved, and the inside of the cup body can be visualized; the coaster is sucked onto a tea tray, the coaster has certain height when folded up, the bottom of a teacup is never stained by water when the water in the tea tray exceeds the coaster, the coaster need not be picked up when the water in the tea tray is poured out, and great convenience is brought.