Abstract: The present research project was conducted to study the effects of varied substrata on the development of R. marginatus. Rhynocoris marginatus was mass reared on five different substrata viz., untreated plastic, tissue and glutting papers, sand and stone, litter and strip, and green leave and stem. The stadial periods of nymphal instars of R. marginatus reared on dry litter with strip ad green leaves with stem were greatly shortened over plastic, tissue and glutting papers, and sand with stone substrata. Green leaves with stem supported better survival than substrata such as plastic, sand with stone, tissue and glutting papers and dry litter with strip. Preoviposition period was shortened in the green leaves with stem and tissue and glutting papers substrata. The fresh adult body weights were slightly higher for R. marginatus reared on four varied substrata than those reared on untreated plastic substrata. Significantly the highest fecundity was found in the green leaves with stem substrate category.