목적: During endoscopic thyroid surgery via transaxillary approach, sometimes we experienced difficulties in transaxillary thyroidectomy for patients who were obese with short and thick neck feature.Much more time is usually needed to get clear operation field and to expose upper pole area in those patients. Some literatures about vocal outcomes after endoscopic thyroidectomy reported no significant difference after surgery but we wondered if whether there is some factors which have negative effect to vocal outcomes, especially for pitch lowering after surgery. 방법:A retrospective review of the medical records and pre-operative CT images of the patients who were treated with transaxillary total thyroidectomy for papillary thyroid cancer from 2010 to 2014 was done. We investigate neck length(measured in CT scan, distance from suprasternal notch to hyoid bone), BMI, operation time, thyroid volume and voice outcocmes. All those patients had pre-operative and post-operative acoustic voice anlaysis within 1 month after surgery. Totally 59 patients were enrolled in this study and we classified those patients into two subgroup by pitch lowering group and no pitch lowering group. Pitch lowering group was defined as patients who showed lowered SFF(speaking fundamental frequency) more than 12Hz at post-op 1 month. 결과:Pitch lowering group showed shorter neck length than no pitch lowering group(98.6cm, 111.2cm for each group) and it had statistical signifance(p- value=0.02). Operation time had correlation with length of neck, but it did not show stastical difference between two groups(151.7 minutes in pitch lowering group vs 132.8 minutes in no pitch lowering group, p-value=0.07). Analysis of acoustic data from 3 months after sugery, we found no significant difference in SFF between two groups(p-value=0.10) 결론:When we do endoscopic thyroid surgery via transaxillary approach, more concerns for voice should be needed in patients with short neck feature.