The aim of this study was to investigate the effects of an 8-week lumbar spinal stabilization exercise program on pain, trunk muscle endurance, and postural stability in women with benign joint hypermobility syndrome (BJHS). Women with BJHS were randomly allocated into exercise (n = 20) and control (n = 18) groups. The lumbar spinal stabilization exercise program was carried out 3 days a week for 8 weeks. BJHS with Brighton criteria, musculoskeletal pain intensity with Visual Analog Scale, trunk muscle endurance with McGill's trunk muscle endurance tests, and postural stability as static and dynamic while eyes open and closed with Biodex Balance System SD were evaluated. Chi-square test, independent sample t test, Mann-Whitney U test, and Wilcoxon test were used for statistical analysis. It was shown that most of the patients with BJHS had low back (exercise group 40.0%; control group 22.2%) and knee pain (exercise group 15.0%; control group 22.2%). After the program, pain intensity, and static and dynamic stability scores (eyes closed) decreased, and trunk muscle endurance scores increased in the exercise group. There was no difference for all parameters in the control group. Pain intensity, trunk muscle endurance, and only dynamic stability (eyes open) improved in the exercise group in comparison to the control group. The lumbar spinal stabilization exercise program improved pain complaints, postural stability, and trunk muscle endurance of women with BJHS. The program can be used for general pain relief, trunk muscle weakness, and postural impairment in women with BJHS.