Piper nigrum L., is considered the “King of Spices” throughout the world due to its pungent principle piperine. Peppercorn of Piper nigrum as a whole or its active components are used in most of the food items. Different parts of Piper nigrum including secondary metabolites are also used as drugs, preservative and natural control agents. Biologically Piper nigrum is very important specie. The biological role of the specie is explained in different experiments that peppercorn and secondary metabolites of Piper nigrum can be used as Anti-apoptotic, Anti-bacterial, Anti-colon toxic, Antidepressant, Antifungal, Anti-diarrhea, Anti-inflammatory, Anti-mutagenic, Anti-metastatic activity, Anti-oxidative, Anti-pyretic, Antispasmodic, Anti-spermatogenic, Anti-tumor, Anti-thyroid, Ciprofloxacin potentiator, Cold extremities, Gastric ailments, Hepatoprotective, Insecticidal activity, Intermittent fever and Larvicidal activity. Other roles of this specie includes protection against diabetes induced oxidative stress: Piperine protect oxidation of various chemicals, decreased mitochondrial lipid peroxidation, inhibition of aryl hydroxylation, increased bioavailability of vaccine and sparteine, increase the bioavailability of active compounds, delayed elimination of anti-epileptic drug, increased orocecal transit time, piperine influenced and activate the biomembrane to absorb variety of active agents, increased serum concentration, reducing mutational events, tumor inhibitory activity, Piperine inhibited mitochondrial oxidative phosphorylation, growth stimulatory activity and chemo-preventive effect. The biological role of Piper nigrum can provide the peppercorn or other parts can be used as crude drug for various diseases while the secondary metabolites such as piperine can be used for specific diseases.