Abstract The effects of neemarin at 5, 10, 15 and 20 mg l −1 on the life table indices of Plutella xylostella (L.) were studied on cauliflower in the laboratory. Survivorship was increased with increasing concentrations. A total of 69% eggs hatched at 20 mg l −1 compared 85% in the control. Mortality ( d x ) of 1st instars was higher than the other instars in both exposed and unexposed individuals. Life expectancy ( e x ) was high in the untreated control and reduced at 20 mg l −1 . Development times of immatures were prolonged to 32 days at 20 mg l −1 as compared to 18.6 days in the untreated control. Neemarin significantly reduced the emergence of adults. Potential fecundity ( P f ) was 34 females/female/generation at 20 mg l −1 and 92 in the control. The net reproductive rate ( R 0 ) was significantly reduced with the increase in concentration. The intrinsic rate of increase ( r m ) and finite rate of increase ( λ ) were significantly decreased at 20 mg l −1 as compared to other concentrations tested and in the control. Mean generation time ( T c ) and corrected generation time ( τ ) were prolonged at 20 mg l −1 and significantly differed to those of the untreated control. Doubling time (DT) was significantly extended to 28.4 days at 20 mg l −1 as compared to 6.1 days in the control.