The determination of resistance level was done at five concentrations of profenofos insecticide (0.0004%, 0.0008%, 0.0016%, 0.0032%, 0.0048%) and one control against C. pavonana larvae from cabbage plantation. The concentrations of synthetic insecticide applied was expected to cause mortality 0 < x < 100 % that determined based on preliminary test. The method used to evaluate resistance level was similar to that used to determine the susceptibility of standard insect. Based on mortality of larvae, probit analysis was used to determine LC50 of profenofos insecticide to field population of C. pavonana.