Polyhexamethylene biguanide hydrochloride (PHMB) is a chemical biocide which is a polymer utilized in a wide variety of antimicrobial applications. This review provides a comprehensive literature of PHMB features from synthesis methods,mode of action, antimicrobial effects and safety considerations to both humans and environments. Effectiveness against cellular organisms is due to the basic biguanide group attached to a flexible spacer, a hexamethylene group. PHMB is a disinfectant with a broad spectrum of inducing cell death by disrupting cell membrane integrity. It is an environmentally friendly product noncorrosive and nontoxic to both humans and animals. It is used as a preservative in cosmetics, personal care products, fabric softeners, contact lens solutions, hand washes, and more. In cosmetics, the preservation of fruit and vegetables. It is also used to preserve wet wipes; to control odor in textiles; to prevent microbial contamination in wound irrigation and sterile dressings; to disinfect medical/dental utensil and trays, farm equipment, animal drinking water, and hard surfaces for food handling institutions and hospitals; and to deodorize vacuums and toilets. This agent can work at low concentrations with very fast action with a broad spectrum of action in addition of its wide acceptance and exploitation for potential multi-purpose functional use. It will be promising for advanced environmental treatments including food disinfection, water disinfection, surface disinfection, and meet the criteria for an ideal antimicrobial agent.