Piper longum L. is a well known spice plant belonging to the family Piperaceae with high pharmacognosy potential, but it is becoming threatened due to overexploitation. Thus, this investigation aims to standardize a cost effective protocol for in vitro propagation of this economically important plant. Internodal segments were used as explant for callogenesis in Murashige and Skoog medium with 3% sucrose and 0.8% agar, with NAA or 2,4 D. Optimum callus induction was observed in MS medium with 5.0 mg/L NAA. Calli were subcultured on shoot regeneration media containing different concentrations of cytokinin (KIN/BAP) along with 0.1 mg/L NAA. Best shoot regeneration was obtained on MS media supplemented with 2.0 mg/L KIN and 0.1 mg/L NAA. Induced shoots were rooted in either NAA or IBA and highest rooting was induced in MS medium enriched with 0.5 mg/L NAA. Rooted plantlets were acclimatized and 88% of hardened plants survived. Field emission scanning electron microscopic showed that regeneration from callus had occurred by somatic embryogenesis. A comparative study on identification and quantification of piperine (the chief alkaloid of the cultivar) were done from root and fruit of both in vitro and in vivo grown plants through Reverse Phase-High Performance Liquid Chromatography method. In vitro grown fruit was found to have the maximum amount of piperine. © 2022, The Author(s), under exclusive licence to Springer Nature B.V.