This chapter discusses the normal structure and the disorders of the male reproductive system. Contents of the scrotal sac include the testicle and epididymis along with lower end of the spermatic cord and the tunica vaginalis that forms the outer serous investing layer. The seminiferous tubules drain into collecting ducts which form the rete testis from where the secretions pass into the vasa efferentia. Cryptorchidism or undescended testis is a condition in which the testicle is arrested at some point along its descent. Non-tuberculous granulomatous orchitis is a peculiar type of unilateral, painless testicular enlargement in middle-aged men that may resemble a testicular tumour clinically. Spermatic granuloma is the term used for development of inflammatory lesions due to invasion of spermatozoa into the stroma. Torsion of the testicle may occur either in a fully-descended testis or in an undescended testis. The penis is covered by skin, foreskin (prepuce) and stratified squamous mucosa. Hypospadias is a developmental defect of the urethra in which the urethral meatus fails to reach the end of the penis, but instead, opens on the ventral surface of the penis. Cancer of the prostate is the second most common form of cancer in males, followed in frequency by lung cancer.