Abstract: A booster chair assembly includes a base that has a top side and a bottom side. A plurality of posts is attached to and extends upwardly from the base. The plurality of posts includes a first front post, a second front post, a first rear post and a second rear post. Each of the posts is selectively telescoping so that a height of each of the posts is adjustable. Each of the posts has a top end. The posts each include a bottom portion and a top portion. The bottom portions are each is slidably extendable into a corresponding one of the top portions. A seat is attached to each of the posts and is horizontally orientated. The seat is attached to the top portions of the posts. A backrest is attached to and extends between the first and second rear posts.