Weeds impose significant damages to farmers every year. Chemical control is one of the most conventional methods to control weeds. All insects inhabiting plants may be affected by herbicide applications. Although it is not expected that affect herbicides due to different insects mode of action of insecticides and herbicides, but they can cause destructive effects on them. The aim of current study is to determine lethal and sub-lethal effects of three conventional herbicides in rapeseed farms, including clopyralid, haloxyfop-R-methyl, and glyphosate, on the cabbage aphid ,Brevicoryne brassicae , as an important pest and its parasitoid wasp , Diaeretiella rapae . Clopyralid and haloxyfop-R-methyl herbicides did not show a lethal effect on the cabbage aphid and its parasitoid wasp, while the value of glyphosate for the aphid and wasp were 8516.45 and 14685.62 mg a.i/L, respectively. Recomended dose for clopyralid and haloxyfop-R-methyl herbicides and the for glyphosate were used to evaluate the sub-lethal effects and life table parameters for these concentrations were determined. None of tested herbicides with selected concentrations caused a sub-lethal effect on the first generation of cabbage aphid. In the second generation, haloxyfop-R-methyl caused a significant increase in intrinsic rate of increase, finite rate of increase, net and gross reproductive rate, fecundity, adult female longevity, oviposition period and longevity. and it also caused an increase in the age-specific survival rate, age-specific fecundity, life expectancy and age-stage-specific survival rate. Clopyralid and glyphosate reduced the net and gross reproductive rate, mean generation time, fecundity, adult female longevity, oviposition period, age-specific survival rate, age-specific fecundity, life expectancy. Furthermore, glyphosate reduced the aphid longevity in comparison with the control, but clopyralid did not show a significant difference. Total Free carbohydrates in the second generation of aphid treated with haloxyfop-R-methyl increased significantly in comparison with control, while the total protein in the treated aphids was decreased. Haloxyfop-R-methyl and clopyralid also changed the quality of host plant dramatically. Haloxyfop-R-methyl caused reduction in organic material percentage and carbon to nitrogen ratio. It also increased the amount of hydrogen peroxide and total phenol content of cabbage plant. In addition to these changes, clopyralid caused a significant reduction in total amount of plant protein. In addition to biochemical parameters of the host plant, biochemical-parameters of aphids were studied on the treated cabbage plants. Using treated plants to determine life table parameters, it was found that both herbicides caused indirect effects such a reduction in net and gross reproductive rate, mean generation time, fecundity, adult female longevity, oviposition period, and longevity. Clopyralid herbicide had decreased gross reproductive rate, fecundity and oviposition period more than haloxyfop-R-methyl. Treated host plants caused a significant reduction in the aphid intrinsic rate of increase and finite rate of increase. Sub-lethal effects of glyphosate on the parasitoid wasp , D.rapae , were studied and the results showed negative effects on bioparameters of this insect. This herbicide caused a significant reduction in percentage of adult emergence and sex ratio and also, reduction in. age-specific survival rate and age-specific fecundity. Key words : Sub-lethal effects, Fertility life table,Pesticides, Biochemical parameters