This chapter mainly focuses on the effect of drugs on rabbit eye. The Iris is composed of two types of muscle fibers, the circular and the radial muscles. The circular fibers are supplied by parasympathetic nerve fibers (cholinergic) and the radial ones are innervated by sympathetic nerve fibers (adrenergic). The stimulation of sympathetic and parasympathetic nerves produces mydriasis and miosis respectively and their paralysis produces opposite effects. Drugs which simulate the effects of autonomic nervous system can produce the above mentioned effects. This experiment uses a few such drugs on the rabbit eye. A detailed discussion on the active and passive miotics and mydriasis and local anesthetics has been also given in this chapter. Two well-illustrated tables and three well-labeled figures related to structure of eye, muscle fibers of eye and instillation are also presented in this chapter.