Ninety compounds structurally related to those compounds found in previous tests to be highly repellent to stored product insects were evaluated as potential repellents of the red flour beetle Tribolium castaneum (Herbst). Thirty-three of the 90 compounds were as repellent or more so than the pyrethrins-piperonyl butoxide combination used as a standard for comparison. Eight of 12 peroxycarbamic acid and 9 of 11 benzotriazin compounds tested were highly repellent to the test insect. N-Butylsulfenyl N,N- dimethyldithiocarbamate (peroxycarbamic acid, dimethyltrithio-, butyl ester) produced the highest average repellency recorded in standard repellency tests at this laboratory.