The house fly, Musca domestica L., is one of the most important medical and veterinary pests and the most common insects in the human habitat which has developed resistance to most synthetic insecticides. This pest in the livestock buildings has caused annoyance and leads to a decrease in productivity. The house fly is a mechanical vector of more than 100 different pathogens such as bacteria, protozoa, viruses and nematodes. Pyrethroid insecticides are the major insecticides in the houseflie control, and plant essential oils are suitable replacements for synthetic insecticides that could be used against houseflies. The present study was aimed to evaluate the toxicity of several essential oils on the pyrethroid insecticides susceptible and resistant flies. Five populations were collected from dairy farms in Isfahan province, a susceptible population was also house fly collected from Chaharmahal and Bakhtiari province (Koohrang). The resistance ratios to pyrethroids in the collected populations were estimated 45- to 180-fold in resistant to tested pyrethroids. Pre-treatment of the populations with PBO, DEM, and TPP synergists were increased the toxicity of permethrin from 1.6- to 8.4-folds. A significant difference was observed between the enzyme activity between resistant populations and susceptible population. In this study,a partial fragmant of the voltage-gated sodium channel in were sequenced, and the L1014F substitution (CTT/TTT) was found to be associated with pyrethroid resistance. Between 26 tested essential oils using topical and fumigation biossays, Zataria multiflora , Rosmarinus officinalis , Mentha pulegium , Eucalyptus cinerea , Thymus vuldaris L. showed the highest insecticidal activity. Then, 12 essential oils with to lowest LC 50 were evaluated on the susceptible and two pyrethroid resistant populations (Fazil and Fka). The selected essential oils shewed a relativity high toxicity against both susceptible and resistant population. But, the LC 50 values significant differente. The efficacy of emulsifiable for six essential oils ( Z. multiflora , R. officinalis , M. pulegium , E. cinerea , T. vuldaris , C. sinensis ), with the hight lethal effect in topical and fumigation bioassay was also evaluation Laboratory and semi-field conditions the formulation of essential oil of Z. multiflora (LC 50 = 1.9, LC 95 = 28 ml / l) showed the highes lethal activity. In the semi-field conditions, formulations of Z. multiflora , R. officinalis , M. pulegium , E. cinerea , T. vuldaris , C. sinensis caused mortality rate. evaluation of the efficiency of the binary mixture of essential oils ( C. sinensis + E. cinerea , C. sinensis + R. officinalis and R. officinalis + M. pulegium ) were found the most effective mixtures in the laboratory and semi-field conditions against the house fly. Based on the results essential oils could be used in integrated pest management of house fly and management its resistance to pyrethroid insecticides. Key Words : detoxification enzymes, insecticides resistance, point mutations, biopesticides, resistance management