The aim of the study was to check the effect of Carum carvi L. essential oil and L-carvone on the emigration, repellence and mortality of Sitophilus oryzae L. In the experiments with caraway essential oil, concentrations of 0.1%, 0.5% and 1% were used, and concentrations of 0.05, 0.1, 0.5 and 1% were used with L-carvone. We assessed whether, in what concentrations and after what exposure time the substances acted on S. oryzae as repellents and/or insecticides. The laboratory tests were carried out at 29 ± 1 °C with 60 ± 5% relative humidity (RH). The deterrence, mortality and abundance of insects were noted after 1, 2, 3, 4, 5, 24 and 48 h. For caraway essential oil and L-carvone, the highest repellency was not shown in the highest concentrations that were used in the tests but in the lower concentrations of 0.5% and 0.1%, respectively. In all used concentrations, caraway essential oil showed repellent effects on S. oryzae. The highest repellency (60–98%) was caused by 0.5% caraway essential oil after 1, 2, 3, 4 and 5 h of research and by 0.1% L-carvone (16–100%). The highest mortality of S. oryzae was caused by 0.5% caraway essential oil and 1% L-carvone. L-carvone at a concentration of 0.05% did not cause mortality in S. oryzae. In conclusion, the greatest repellent effects on S. oryzae were caused by lower doses of caraway essential oil and L-carvone. These compounds do not show the normal relationship described in the previous literature on warehouse pests, in which the repellency increased with increasing concentrations of the tested plant material.