PURPOSE: To provide a door trim mounting structure whereby door trim can readily be mounted by means of movement in one direction only and no upper limit position is imposed to a clip.

CONSTITUTION: Installation of door trim 25 is completed simply by horizontally moving the door trim 25, inserting its horizontal insertion portion 29 between an upper horizontal flange 17 other than an embossed portion and the upper holding portion 36 of an inner seal 34, and inserting the upper holding portion 36 of the inner seal 34 in a receiving portion 30 located on the side of the door trim 25; i.e., installation of the door trim 25 can be completed simply by moving the door trim 25 in one direction (horizontal), so the installation work is easy and automation using a robot is easy to achieve. Therefore, no upper limit position is imposed to a clip 19a, for example.