Spaces open to the public should meet physically in the best manner the quality of life, health, security and prosperity of all their users. This necessity also makes the accessibility of the space obligatory. Public spaces should be open to the experience of all users by keeping the principle of equality in the forefront. Especially, it is rather important for museums, as one of the cultural spaces open to the public, to fulfill in its full meaning these requirements mentioned. Consequently, when the museums, which are gradually increasing in numbers in the present-day, are taken into consideration, then it is important for both the users to be informed related to these spaces and for the institutions to consider in a critical manner with an objective viewpoint on what is the situation of researching and sharing the accessibility of these structures. The operations research studies made are acquiring importance in this meaning. In this study made, an evaluation of the accessibility of the PTT (Post, Telephone and Telegraph) Stamp Museum located in Ankara was made through an operations research realized by the researchers with the use of wheelchairs and the TS 9111 criteria. Especially, when it is thought that remaining dependent only on the standards would not overlap very much with theory and practice and because it would be insufficient, the operations research was held more in the forefront in this study.