BACKGROUNDThyroid carcinoma (TC) is the ninth most common site of all cancers in women in the world and the second most common malignancy in Saudi Arabia. This reports updates data on the epidemiology of the disease in Saudi Arabia.OBJECTIVEDescribe and interpret changes in the frequency of TC to compare with other populations and determine proportions of certain histological types of TC.DESIGNMedical record review.SETTINGMilitary hospital in Jeddah, Saudi Arabia.PATIENTS AND METHODSWe reviewed the pathological and clinical records from January 2000 to December 2017 of patients with TC.MAIN OUTCOME MEASURESFrequency and types of TC.SAMPLE SIZE347 patients.RESULTSOver the 18-year period, out of 456 patients with TC, 347 patients had sufficiently complete records: 275 (79.3%) were female and 72 (20.7%) were male for a female to male ratio of 3.8:1. The mean (SD) age at surgery of all patients was 45.2 (16.0) years. There were 287 (82.7%) cases of papillary TC. The next common malignancy was follicular TC with 32 (9.2%) cases followed by Hurthle cell cancer with 11 (3.2%) cases. Lymphoma was found in only 7 (2%) cases. All TC types occurred at a younger age in females than males except for lymphoma. All TC types occurred with the greatest frequency in the fourth and fifth decades. There was a 2.3-fold increase in the number of TCs from 8 (2.3%) in 2000 to 26 (7.5%) in 2017. The rate per 100 000 residents of Jeddah increased for the period from 2000 to 2002 from 1.6 to 3.4 for 2015–2017. Papillary TC cases in females accounted for most of the increase.CONCLUSIONOur findings are consistent with similar studies worldwide. Etiological factors promoting the rise in TC must be investigated and may provide insight in developing suitable management strategies for the Saudi population.LIMITATIONSmall sample size and retrospective over a long period.