Selected weed species were assessed for assessing their suitability as energy production sources using chemical conversion routes. The physical and chemical properties of 26 weed species were characterised. Physical characterisation included determination of number of branches, plant height, plant weight, stem diameter, density and chemical characterisation included determination of moisture content, ash content, volatile matter content and fixed carbon content. Abutilon indicum G.Don, Achyranthes aspera L. and Dyschoriste nagchan, Nees. were identified for thermochemical gasification and five weed species were selected for biochemical gasification. The rate of gas production from Abutilon indicum, G.Don., Achyranthes aspera, L. and Dyschoriste nagnchann, Nees. in thermochemical conversion process was 1.709, 2.212 and 2.246 m(3) kg(-1), respectively and a maximum biogas production of 20.13 l kg(-1) was observed for Achyranthes aspera, L. in a biochemical conversion process.