Leaves and flowers of Catharanthus roseus L. are evaluated for larvicidal activity against Anopheles stephensi L. The larval mortality was observed at 24 and 48 hrs of time exposure. Highest larval percent was observed to be found in the flower extract of Catharanthus roseus L. plant with 100% mortality at
100mg/l concentration. LC50 value was calculated against different
concentrations. It is recorded that lowest LC50 value was observed in the Catharanthus roseus L. flowers followed by leaves i.e. 37.15mg/l and 67.61mg/l respectively after 24 h of exposure time and 26.92mg/l, and 35.48mg/l. respectively at 48 h of exposure time. The present study indicates that phytochemical derived from Catharanthus roseus L. flower extracts are effective mosquito vector control agent and the plant extracts may be useful for further integrated pest management programme.