Height-adjustable dinner chair for children

The utility model discloses a height-adjustable dinner chair for children. The dinner chair comprises a chair body and a chair frame with an upper beam and a lower beam, wherein first installation holes are arranged on chair legs of the chair body; the dinner chair is provided with a first working position, a second working position and a third working position, and the chair body is separated from the chair frame under the first working position; the chair body is placed on the upper beam under the second working position, and the first installation holes and second installation holes are inserted for fixing through inserting pins; the chair body is placed on the lower beam under the third working position, the first installation holes and third installation holes are inserted for fixing through fixing pins; and the chair frame further comprises a middle beam arranged in the chair frame, the dinner chair further has a fourth working position, the chair body is placed on the middle beam under the fourth worki