This chapter focuses on the pathology of the endocrine system, encompassing disorders of the pituitary, thyroid, parathyroid, and adrenal glands. The chapter begins with the thyroid gland, discussing conditions such as goiter and Hashimoto’s thyroiditis, highlighting their histological and clinical presentations. Pathologies of the pituitary gland, including pituitary adenomas, are examined with a focus on hormonal dysregulation and mass effects. Adrenal gland disorders, such as Cushing’s disease, Addison’s disease, Conn’s syndrome, and the severe Waterhouse–Friderichsen syndrome, are discussed, emphasizing their pathophysiology and systemic implications. The chapter also explores neoplastic conditions such as neuroblastoma, delving into their diagnostic markers and clinical relevance. Disorders of the parathyroid glands are analyzed for their impact on calcium metabolism and associated systemic effects. With a blend of pathological insights and clinical perspectives, this chapter provides a comprehensive understanding of endocrine system disorders, aiding in early detection, effective treatment, and management strategies.