Treatment of early and late third instar larvae of economically important insect C. megacephala with the ageratochromene precocene II resulted into precocious metamorphosis. The other effects included mortality, production of pupal-adult mosaics, reduction in percentage of adult emergence and formation of non-viable deformed adults that died after a few hours of emergence. The application of precocene II adversely hampered the normal growth, development and metamorphosis of the insect and the results show that precocene II has vast potential for excellent control of this insect of medico-veterinary importance and can be used in insect pest management programs.