Background: the endocrine system releases hormones that help control body functions including the body's ability to change calories into energy that powers cells and organs. The endocrine system influences heart beats, bones and tissues growth. It plays an important role in controlling blood glucose. Moreover, it is associated with many disorders including thyroid disorders, growth disorders, and sexual dysfunction. All endocrine glands release hormones into bloodstream. Objective: The objective of this study was to define the types of diseases seen at the only endocrine clinic in King Khalid University Hospital (KKUH). Methods: we retrospectively analyzed the diagnosis data of all patients attending the endocrinology clinic of the University Hospital in AL Riyadh city over a 7 weeks' period. Results: The majority of cases had thyroid related diseases (48.6%) while 12.8% had gonadal and growth diseases, 9.2% had Lipid, 7.3% had pituitary diseases, 5.5% were for wrong referrals, 5.5% and 4.9% had adrenal & vitamin D deficiency related diseases respectively. The lowest percentages were 3.7% for parathyroid and 2.8% for metabolic bone diseases. Conclusion: Thyroid related disorders were found to be the most common endocrine disorders presented to KKUH. Almost half of the patients had thyroid related disorders, accordingly we highly recommend that extensive efforts should be in place to recruit experienced residents as well as continuously and efficiently train existing ones on Thyroid related diseases.