The effect of time on mortality of various developmental stages of <i>Stegobium paniceum</i> (Linneaus) at -20°C was studied. Eggs, larvae, pupae, and adult insects were collected and exposed to -20°C for 0-4 hours. Complete mortality was observed for all developmental stages after 1-hour exposure. The use of low temperatures as an alternative to conventional fumigation techniques for the treatment of insect-infested museum objects is discussed in terms of the results of these experimental trials.