Abstract: The present invention relates to a popup installation structure for a sink and to an installation method. The popup installation structure installed in a sink is configured such that an upper protrusion that tightly contacts a drain hole of the sink is formed on a top of the structure, drainpipes are arranged at both left and right sides of an intermediate portion of the structure such that each drain pipe is opened in a transverse direction and has a drain space in communication with an overflow passage formed from a bottom surface of the sink, and a sewer pipe is arranged in a lower portion of the structure such that the sewer pipe is coupled to a drain trap arranged below the basin.