Objective To investigate the thyroid diseases in soldiers(aged 30 years and above)stationed on a certain island,and to clarify the value of ultrasonic diagnosis.Methods Thyroid ultrasonography was performed in 270 soldiers(aged≥30 years)stationed on an island by the high-frequency probe of the Mindray Z6 portable B-mode ultrasound diagnostic instrument.According to the C-TIRADS classification,the proportion of soldiers with thyroid nodules was calculated.Results Thyroid nodules were found in 50 soldiers(18.52%),including 29 cases(10.74%,cystic nodules)of C-TIRADS type 2,15 cases(5.56%,solid or cystic nodules)of C-TIRADS type 3,5 cases(1.85%,solid or cystic nodules)of C-TIRADS type 4a,and 1 case(0.37%,solid nodule)of C-TIRADS type 4b.Conclusion Thyroid ultrasound helps to analyze the causes of thyroid diseases,make grading assessment,and provide suggestions for soldiers stationed on islands.Not only does it clarify the necessity of thyroid ultrasonography in the physical examination,but also provides suggestions to improve the medical environment on islands.