We aimed to investigate whether agoraphobia (A) in panic disorder (PD) has any effects on oxidative and anti-oxidative parameters. We measured total antioxidant capacity (TAG), paraoxonase (PUN), arylesterase (ARE) antioxidant and malondialdehyde (MDA) oxidant levels using blood samples from a total of 31 PD patients with A, 22 PD patients without A and 53 control group subjects. There was a significant difference between the TAG, PUN, ARE and MDA levels of the three groups consisting of PD with A, PD without A and the control group. The two-way comparison to clarify the group creating the difference showed that the TAG, PUN, and ARE antioxidants were significantly lower in the PD with A group compared to the control group while the MDA oxidant was significantly higher. There was no significant difference between the PD without A and control groups for TAG, PUN, ARE and MDA levels. We clearly demonstrated that the oxidative stress and damage to the anti-oxidative mechanism are significantly higher in the PD group with A. These findings suggest that oxidative/anti-oxidative mechanisms may play a more important role on the pathogenesis of PB with A.