Abstract: The red cotton bug, Dysdercus cingulatus, an important polyphagous pest, causes heavy loss to cotton and lady’s finger (bhindi) crops which badly affects the economy of poor farmers. In the present study, the impact of different concentrations of neem based insecticides (NBIs) on coupling, moulting, development, hemocyte, fecundity and egg-hatching of D. cingulatus was evaluated. Various concentrations (0.25, 0.5, 1.0 and 2.5%) and doses (2.5 to 20 μL) of NBIs viz. neemark, multineem and neemazal were prepared by diluting them in acetone were applied topically on the dorsum of the body of nymphs and adults and eggs of different age groups. NBIs causes developmental abnormalities such as prolongation of nymphal periods, ecdysial stasis, formation of adultoids and adults with varied degrees of wing deformities. The delay in moulting of treated nymphs is found concentration, dose and stage dependent. The application of NBIs on cephalic and thoracic regions and on ventral surface of insects showed more sensitivity than on abdominal region and dorsal surface. The NBIs application interrupted the coupling and cause lessening of fecundity and egg-hatching also. Among aforesaid NBIs, neemazal treatment was somewhat more effective. In addition, significant reduction in Total Hemocyte Count (THC) and deformities in hemocyte morphology were also observed in NBIs treated insects. It is assumed that the phenomena like metamorphic developments, coupling and fecundity are controlled by Juvenile Hormone (JH) via regulating the release of allatotropic factor from the brain and all these effects of NBIs are stage specific and concentration and dose dependent. NBIs induced changes in hemocyte contour might be also regulated by the brain hormone.