Purpose: To assess the subfoveal choroidal thickness (SFCT) in patients with Behç et disease (BD) and compare the SFCT in patients with and without OCULAR BD (OBD) and between patients with active and quiescent phases of the Behç et’ s posterior uveitis. Method: This prospective cross-sectional study was conducted on patients with BD (n = 51) between October 2016 and October 2018. Complete OCULAR examinations including slit lamp biomicroscopy and fundus examination with dilated pupils were performed for all patients. The SFCT values were compared between patients with and without OBD. Enhanced depth imaging optical coherence tomography (EDI– OCT) was done to measure the SFCT, and wide field fundus fluorescein angiography (WF-FAG) was performed to evaluate the OCULAR INVOLVEMENT and determine the active or quiescent phases of the Behç et’ s posterior uveitis. The correlation between the changes of SFCT and the WF-FAG scores was assessed. Results: One hundred and two eyes of 51 patients with BD, aged 29 to 52 years were studied. Of these, 23 patients were male. The mean age ± standard deviation in patients with OBD and patients without OCULAR INVOLVEMENT was 38. 71 ± 7. 8 and 36. 22 ± 10. 59 years (P = 0. 259) respectively. The mean SFCT in patients with OBD was significantly greater than in patients without OBD (364. 17 ± 93. 34 vs 320. 43 ± 56. 70 µ m; P = 0. 008). The difference of mean SFCT between the active compared to quiescent phase was not statistically significant when only WF-FAG criteria were considered for activity (368. 12 ± 104. 591 vs 354. 57 ± 58. 701 µ m, P = 0. 579). However, when the disease activity was considered based on both WF-FAG and OCULAR exam findings, SFCT in the active group was higher than the inactive group (393. 04 ± 94. 88 vs 351. 65 ± 58. 63 µ m, P = 0. 060). This difference did not reach statistical significance, but it was clinically relevant. Conclusion: Choroidal thickness was significantly increased in BD patients with OCULAR INVOLVEMENT; therefore, EDI-OCT could be a noninvasive test for evaluation of OCULAR INVOLVEMENT in patients with BD. The increased SFCT was not an indicative of activity in OBD; however, it could predict possible OCULAR INVOLVEMENT throughout the disease course.