To provide a joining structure, the number of parts of which is few and the structure of which is simple and in which no inner member falls off even either under the state that an inner pressure such as a compressed gas is applied from inside or under the environment, in which temperature change or a secular change is large.

In this joining structure of members, a synthetic resin tubular member employed in a coating tool or a writing utensil and an internal member, some part or the whole of which is pressed in the tubular member, and a clearance portion, which does not come into contact with the internal member, is formed at the inside of the opening end of the tubular member.