To provide a chair satisfying the needs of various users.

The chair 1 includes: a first seat part 11; four legs 12 supporting the first seat part 11; a second seat part 13 forming a second seat surface different in height from a first seat surface formed by the first seat part 11; a backrest part 14 extending upward from the rear end of the first seat part 11; two side parts 15 extending from the respective right and left side end parts of the first seat part 11 and backrest part 14; and a partition part 16. The chair 1 allows to selectively have: a first shape wherein the second seat part 13 is horizontally arranged between the partitioning part 16 and the side part 15 so as to satisfy the needs of the user accompanied with a child; a second shape wherein the second seat part 13 and the partitioning part 16 are vertically arranged along the side part 15 so as to satisfy the needs of the user of a large body type; and a third shape wherein only the second seat part 13 is vertically arranged along the side part 15 so as to satisfy the needs of the user carrying a baggage.