The toxicokinetics of single-dose intravenous and intracrop administration of cypermethrin has been described in broiler chickens. Twenty male broiler chickens were distributed in two groups of ten animals each. The animals in the groups mentioned were given cypermethrin in both routes at a single dose of 7.5 mg/kg b.w. Blood samples were collected by the wing vein of chickens at 0.083, 0.25, 0.50, 0.75, 1, 2, 4, 6, 8, 12, 18, 24 and 36 hours after administration of cypermethrin. Determination of serum cypermethrin levels was performed by the gas chromatography-electron capture detection. When the serum concentration-time graph of cypermethrin was evaluated, it was found that this pesticide showed a more convenient distribution tendency in the two-compartment open model. The values of t(1/2 beta), MRT and AUC(0 ->infinity)were 7.35 +/- 0.91 hours, 8.64 +/- 1.59 hours and 8741.98 +/- 1996.66 ng.h/ml, respectively, after intravenous administration of cypermethrin. On the other hand, C-max, t(max), t(1/2a),t(1/2 beta), MRT and AUC(0 ->infinity) values calculated for intracrop applied cypermethrin were 422.75 +/- 99.59 ng/ml, 0.80 +/- 0.15 hours, 0.24 +/- 0.05 hours, 10.97 +/- 2.11 hours, 15.39 +/- 2.56 hours and 4266.51 +/- 967.65 ng.h/mL, respectively. The systemic bioavailability of cypermethrin administered intracrop was 48.80%. From the results obtained, bioavailability of cypermethrin and the MRT at the same time in the body are moderate. These results were considered to be an important indicator in the evaluation and treatment of cypermethrin poisoning in broiler chickens.