© 2019 Turkish Physiotherapy Association. All rights reserved.Purpose: It is known that in conditions where lumbopelvic stability is decreased, postural balance is worsened, the effort required for the neutral position and protecting posture is increased, individuals tire earlier, and the frequency of injury increases. Although it has been highlighted that lumbopelvic stability is important for balance and physical performance, the relationship between M. Transversus abdominus (mTrA) and M. Lumbar multifidus (mLM) and balance and physical performance have not been investigated. We aimed to examine the relationship between postural balance and physical performance and mTrA and mLM muscle thicknesses. Methods: A total of 64 healthy young adults aged 18-25 years were included in the study. Ultrasonographic imaging was used to determine the thicknesses of mTrA and mLM. Biodex Balance System was used for the objective evaluation of static and dynamic postural balance. Physical performance was assessed using the vertical jump test, sidestep test, and shuttle run test. Results: There was a statistically significant correlation between mTrA muscle thickness and general stability index (GSI), anteroposterior stability index (APSI), and side step test (p<0.05). A statistically significant correlation was found between mLM muscle thickness and GSI, APSI, side step test, and shuttle run test (p<0.05). Conclusion: Because the decrease in the lumbopelvic motor control is associated with worsening of balance and physical performance, it is thought that balance end physical performance evaluation should be considered for the lumbopelvic motor control assessment.