Background/aims: Constipation is the most frequent complaint of the digestive tract. It has been reported that approximately half of the patients with constipation have functional defecation disorders (dyssynergic defecation). An important diagnostic tool for the diagnosis of functional defecation disorders is the balloon expulsion test. Normative values have not been widely determined in different populations. We aimed to determine the data which could be indicative of normative values of the balloon expulsion test for healthy individuals in our society. Methods: A total of 116 healthy volunteers were evaluated in. the study (55 men). Subjects were classified into three subgroups according to age (20-39 yrs, 40-59 yrs, >= 60 yrs). Catheters with balloon and application room were standardized, and then a balloon expulsion test was performed in all groups. The results of the balloon expulsion test were statistically compared between groups. Results: The distribution of males/females according to age groups was: 20-39 yrs: 20/22, 40-59 yrs: 20/23, >= 60 yrs: 15/16. The balloon expulsion time was determined as 44.1 +/- 19.0 seconds in male subjects and 56.4 +/- 21.4 seconds in females (p=0.001). An increase in the balloon expulsion time was observed to be related with age in males (p=0.00001); however, no statistically significant difference was shown by age in female subjects (p=0.80). If the entire study group was considered, there was a significant correlation between age and balloon expulsion time (p=0.0001). Conclusions: The balloon expulsion test is a simple procedure to identify impaired evacuation in constipated patients. This study represents the first assessment of the balloon expulsion test in a healthy Turkish population. It has been demonstrated that expulsion should take less than 30 seconds for men younger than 40 years of age and less than 1 minute above 40 years. For women, expulsion should occur in I minute regardless of age. Our results could serve as a valuable resource of normative data.