Black pepper (Piper nigrum L.) is a famous spice of piperaceae family and commonly known as "King of Spices". Black pepper is also called "Indian Long Pepper" and mainly used in dried form and the dried form of pepper fruit is called peppercorns. Black pepper is originated in the tropical evergreen forest of the Western Ghats Mountains in India and commonly used in curry recipes. Many cultivars of black pepper are being cultivated in India. Karimunda is the most popular cultivar in Kerala. The other important cultivars are Kottanadan, Narayakodi, Aimpiriyan, Neelamundi, Kotta, Kuthiravally etc. Black pepper mainly used to treat diseases like diarrhea, fever, asthma, sinus, chronic indigestion, skin disorders, cholera and Ayurvedic and Unani systems use stem and root of pepper as important drug. The antimicrobial activity mainly tested for drug discovery, prediction of therapeutic outcome and epidemiology. Three different varieties of pepper in Kerala were selected for detection of antibacterial activity against E. coli and Bacillus subtilis.