Background: Thyroid disorders refer to benign or malignant condition affecting the structure and function of the thyroid gland that may present as a derangement of thyroid hormone secretion, thyroid enlargement or pain. Thyroid disease is a global health problem and the most common type of endocrine disorders next to diabetic mellitus accounting around 30% to 40% burden of the endocrine disorder.Objective: The present study was aimed to assess the magnitude and pattern of thyroid disorders among patients with anterior neck mass visiting Jimma Medical Center (JMC) based upon clinical decision and serum levels of thyroid function test (TFT) in 2018 G.C. Methods:A cross-sectional study was employed among the sampled 239 patients, with anterior neck mass visiting JMC. Data was collected after written and informed consent was obtained by using structured questionnaire, physical examination and laboratory measurements. TFT was done by measuring serum TSH, FT4, and FT3 levels by electro-chemiluminescence immune assay method at JMC laboratory. Data was entered into Epidata version 3.1 and exported to SPSS version 22 for analysis. The data was processed, summarized and presented in the form of narratives, tables, graphs or figures.Result: A total of 239 patients with anterior neck mass visiting outpatient clinic of JMC were recruited in the study with mean age of 41.83 ± 17.52 SD years ranged from 18 to 90 years. Majority of the patients were females 212 (88.7%) while the left 27 (11.3%) were males; 155 (64.8%) of the study subjects were living in rural part while the rest 84 (35.2%) were from urban. Majority of the patients were belonged to stage II [117 (48.9%)] while others were allocated to stage III [86 (36%)], stage IB [30 (12.6%)] and stage IA [6 (2.5%)]. The mean of TSH was 0.95±49 and 0.83± 56 among males and females respectively while the mean of FT3 (4.58±38 vs. 4.27±86 vs.) and FT4 (15.47±92 vs. 14.98±44) among males and females respectively. The magnitude of signs and symptoms of patients with highest frequency were heat intolerance, irregular pulse, palpitation, cold intolerance, tachycardia, hypertension, weight gain, swelling, poor memory, weight loss and menstrual irregulaty. The discriminated types of thyroid disorders were euthyroidism 83 (34.7%), sub-clinical hypothyroidism 46 (19.2%), sub-clinical hyperthyroidism 42 (17.6%), hypothyroidism 35 (14.6%) and hyperthyroidism 33 (13.8%). Conclusion and Recommendation:Continous assessment of patients with anterior neck mass needs due emphasis for the overall management modality in preventing morbidity and mortality associated due to systemic exacerbation of the disease.