Seven plant species, namely Cassia fistula Linn., Calotropis procera R.Br., Datura alba Ness, Lantana camara Linn., Myrtus communis Linn., Sapium sebiferum Roxb., and Thevetia neriifolia Juss were tested for biological activity at the rate of 5% (5g:100ml) against termites, nettle tree leaf beetle (Diorhabda lusca) and amaltas leaf stitcher (Piesmopoda obliquifasciella). Decoction of these plant species provided significant protection against termites for three months in the field. D. alba and C. procera were the most effective against termites with 62.5% protection. While M. communis and L. camara with 18.5 and 18.75% protection, respectively were the least effective. Similarly, cold water extract of these plant species showed positive biological activity against D. lusca and P. obliquifasciella. After two weeks, maximum cumulative control of 57.87% and 62.96% was observed due to D. alba against D. lusca and P. obliquifasciella, respectively in the laboratory. Likewise, C. procera, C. fistula, L. camara, T. neriifolia, M. communis, S. sebiferum & the control gave 57.41, 49.54, 34.26, 23.61, 18.92, 15.28 & 0.0 and 55.55, 48.14, 33.33, 18.52, 11.11, 11.11 & 0.0 percent control of D. lusca and P. obliquifasciella, respectively. Moreover, C. procera (2.84%), C. fistula (3.24%), M. communis (41.28%), S. sebiferum (27.29%), T. neriifolia (21.56%) and L. camara (2.71%) were comparatively more effective against D. lusca than P. obliquifasciella. But effect of D. alba (8.08%) was otherwise.