p-hydroxy benzoic acid (PHBA) is an organic chemical which can be obtained naturally as well as synthetically. The literature survey reveals its various biological properties viz. antimicrobial, antialgal, antimutagenic, antiestrogenic, hypoglycemic, anti-inflammatory, anti-platelet aggregating, nematicidal, antiviral, antioxidant etc. It is also reported to be used as preservative in many drugs, cosmetic products, pharmaceuticals, food and beverages. Some derivatives of 4-hydroxybenzoicacid are found to possess direct action on Hbs molecules, inhibit acetic acid induced oedema and used in management of sickle cell disease. The present study will give comprehensive information of the biological activities of this p-hydroxy benzoic acid and its derivatives.p-hydroxy benzoic acid (PHBA) is an organic chemical which can be obtained naturally as well as synthetically. The literature survey reveals its various biological properties viz. antimicrobial, antialgal, antimutagenic, antiestrogenic, hypoglycemic, anti-inflammatory, anti-platelet aggregating, nematicidal, antiviral, antioxidant etc. It is also reported to be used as preservative in many drugs, cosmetic products, pharmaceuticals, food and beverages. Some derivatives of 4-hydroxybenzoicacid are found to possess direct action on Hbs molecules, inhibit acetic acid induced oedema and used in management of sickle cell disease. The present study will give comprehensive information of the biological activities of this p-hydroxy benzoic acid and its derivatives.p-hydroxy benzoic acid (PHBA) is an organic chemical which can be obtained naturally as well as synthetically. The literature survey reveals its various biological properties viz. antimicrobial, antialgal, antimutagenic, antiestrogenic, hypoglycemic, anti-inflammatory, anti-platelet aggregating, nematicidal, antiviral, antioxidant etc. It is also reported to be used as preservative in many drugs, cosmetic products, pharmaceuticals, food and beverages. Some derivatives of 4-hydroxybenzoicacid are found to possess direct action on Hbs molecules, inhibit acetic acid induced oedema and used in management of sickle cell disease. The present study will give comprehensive information of the biological activities of this p-hydroxy benzoic acid and its derivatives.