The aim of this study was to investigate the relationship between tinnitus loudness level (TLL) and internal jugular venous flow rate (IJVFR) in tinnitus patients with a unilateral high jugular bulb detected by temporal bone high-resolution computed tomography (HRCT). The study group consisted of 24 adult patients (13 male, 11 female) with a unilateral high jugular bulb. One ear suffered from tinnitus with a high jugular bulb was included into the study group. The ears without tinnitus and no high jugular bulb on temporal bone HRCT comprised the control group. All patients were evaluated with a history and physical and otolaryngologic examinations, and, using a questionnaire, TLLs were detected. The patency and flow rates in the internal jugular veins were measured by right and left internal jugular venous Doppler ultrasonography. The TLLs were "very quiet" in 1 (4.1%) patient, "intermediate loud" in 17 (70.9%) patients, and "very loud" in 6 (25.0%) patients. IJVFRs were not different in the study and control groups. In the study group, IJVFRs were not correlated with age. There was no relationship among TLLs and IJVFRs, dominance, dehiscence, and bony septum thickness between the high jugular bulb and the middle ear. TLLs were not affected by IJVFRs, dominance, dehiscence, and bony septum thickness in patients with a high jugular bulb. More detailed studies should be undertaken to determine the reason for the different TLLs in patients with a high jugular bulb.