“Mo Lum” is a culture of the performing arts in the northeastern region of Thailand. “Mo Lum” means a person who is skilled at telling stories or literature by singing. Mo Lum can be divided into two main types: Mo Lum Klon and Mo Lum Mu. Currently, Mo Lum Mu (a group of Northeastern-style singers and actors) is the most popular in Thailand, and Mo Lum Mu has still progressed and been contemporary in their performances. About 70 years ago, there were 5–8 members in the troupe, but now some groups have more than 300 members. Mo Lum Mu currently has both beautiful and spectacular musical performances, and there will probably be traditional performances as well. It is interesting to note that during a Mo Lum Mu performance, space must be divided into three main areas: an area for viewers of the performance, a stage area for performances, and a backstage area for performers. As a result, the objective of this paper is to study the development of spatial management in Mo Lum Mu performances and to study the use of space by performers and audiences while performing. This research has chosen to study Mo Lum among the Ratanasil Inta Thaiyarat group. Mo Lum Mu has the longest history and is still active, after 76 years. This study has researched information from related documents and went to the area to conduct field surveys. Both participant and non-participant observations. There were interviews to develop a compilation of photographs from each period and present them with drawings, plans, and other things about the architectural space of Mo Lum Mu. This research reveals that from the past to the present, free space management systems have been complex in front of the stage, on the stage, and especially behind the stage. The arrangements were noticeably more complicated. Some are related to the function of each part, and some are related to social status and psychological value, such as the Buddha shelf zone, singer and actor zones, space for collecting props and musical instruments, as well as the kitchen zone.