Techniques of population estimation with acceptable limits of percision were investigated for the adult beetle of Tribolium castaneum. Two techniques were tested : direct counting of insects on sample units of known size and method of capture, marking, release and recapture. About 1082 cm3 of whole-wheat flour together with 1095 adult beetles were placed into plastic cylindrical vessel, 21.5 cm in diameter and 12 cm in height. Each sample was taken filling 1.8 x 5 cm glass tube with flour together with beetles. The result of estimations in different sample sizes was shown in Table 1 . In the present study sample size calculated for 10 % admissible error was 54. The capture-recapture method was employed : one hundred of beetles were marked on the elytra with white lacquer and released. The result of estimations in different numbers of marked beetles recaptured was shown in Table 2. To increase degree of precision, it was recommended to increase number of beetles marked rather than that recaptured
