The parasitic nematode, Ascaris suum, produces eggs that can survive desiccation, exposure to disinfecting chemicals, and temperatures up to 55 ºC, making decontamination difficult. The viability of Ascaris suum eggs to hot temperatures is well documented, but little information exists on survival in cold temperatures. To test the cold tolerance of A. suum eggs, samples of egg and water solution were stored at 4 ºC, -4 ºC, -20 ºC, and -80 ºC. At set time points between 30 minutes to 300 days, samples were removed from the freezer and allowed to thaw and develop at room temperature. Following a three to six week development period, eggs were examined and the developmental stage was scored. We then assessed the impact of time and temperature on the fraction of eggs that developed and found that eggs exposed to low temperatures exhibited reduced development compared to controls held at room temperature. The information from this experiment will help evaluate the effectiveness of freezing as a mode of infection control and potentially serve as a model for the freeze tolerance of other closely related species, such as the human pathogenic parasites Ascaris lumbricoides and Baylisascaris procyonis