Background and Objectives: Ankle sprain is one of the most common injuries in valleyball players that reduces the strength of ankle muscles and this leads to reduced function and balance, and results in recurrence of injury. Therefore, the purpose of this study was to determine and compare balance, function, strength and endurance of selected core muscle groups in male volleyball players with and without an ankle sprain. Materials and Methods: In this descriptive study, 40 male volleyball players in Bandar Abbas clubs in 2018 with age range of 20-27 were randomly selected and divided into two groups with and without chronic ankle sprain. The number of subjects in each group was 20. McGill test, manual muscle testing (MMT), Y balance test, figure-eight jump and Side-to-Side Hop tests were used to measure trunk endurance, strength, balance and function of volleyball players of the two groups, respectively. Independent t-test was used to analyze the data. Results: Significant differences were observed between the groups in hip abduction (p=0. 006), external rotation strength (p=0. 020), the Sorensen test (p=0. 018), 60° trunk flexion test (p=0. 032), forward bridge (p=0. 031), inferolateral (p=0. 021) and inferomedial (p=0. 008) of the Y balance test and total score of Y balance test (p=0. 019), figure-eight jump (p=0. 023) and Side-to-Side Hop test (p=0. 033). Conclusion: The findings showed that the ankle sprain, if not accompanied by rehabilitation program, may have negative effect on strength, endurance, balance and performance of athletes. Accordingly, rehabilitation and balance exercises are recommended to prevent the possibility of recurrence.