We investigated 25 patients with panic disorder (PD group) and 19 healthy subjects (Control). We selected 9 patients with eminent suffocation complaints (PDr subgroup) and 9 patients without respiratory complaints (PD subgroup). We determined the levels of anxiety (State and Trait Anxiety Inventory of Spielberger), depression (Beck), stressor events during last year (Holmes) and autonomic disturbances signs (Vegetative Profile). We recorded airflow, thoracic respiratory movements and electrocardiogram at rest. The comparisons of the respiratory parameters between PD group and Control did not show significant differences. Patients had higher levels of anxiety and autonomic disturbances. The PDr subgroup had highest levels of anxiety and autonomic disturbances vs Control and PD subgroup. We did not establish differences of the respiratory parameters between PD subgroup and Control. The PDr had decreased respiratory frequency and increased time of the inspiration vs PD subgroup. These findings are accorded with “suffocation false alarm” (2, 3) and “misinterpretation of body sensation” (1) theories of Panic Disorder. The symptoms of suffocation are misinterpreted like dangerous, this fact can increase anxiety and change breathing pattern in a part of Panic Disorder patients.