The family Ptinidae (Coleoptera) contains approximately 2,800 described species and includes larvae and adults that feed on animal and vegetable organic matter. Among the 81 species recorded for Brazil is Lasioderma serricorne (Fabricius, 1792). This cosmopolitan species is popularly known as the smoke beetle and it infests a large number of stored products such as tobacco, dried fruits and meat, grains, bran, flour, and industrialized dog food, being considered of extreme importance in places that store seeds and soybeans. The objective of the present work was to investigate the occurrence of L. serricorne in an artificial diet of the clerid Necrobia rufipes (DeGeer, 1775). In the Systematics and Bioecology laboratory at the State University of Paraíba (Campina Grande, Paraíba), live adults of L. serricorne were observed in rearing cages of N. rufipes. As soon as the clerid's diet items arrived at the laboratory, they were removed from the original packing and stored in sterile screw-top containers. The infestation by L. serricorne could not have occurred in the laboratory, as the N. rufipes rearing cage was covered with voile fabric tied with a rubber band. In this way, the question is whether the diet (composed of soy flour, beer yeast, dog food and bacon) had been infested by L. serricorne prior the purchase. To test this hypothesis, each food item was individualized in cap-sealed plastic containers (200 ml) that were kept in consistent environmental conditions of temperature and humidity. The containers were checked daily for the presence of L. serricorne. The first adult emergences were recorded in soy flour after 23 days (n = 80 adults) and in dog food after 25 days (n = 35 adults) of purchase. The collected specimens were kept in 70% alcohol and species identification was confirmed through comparison with literature. This is the first record of L. serricorne in soy flour and dog food for the state of Paraíba, Brazil.