To discuss the effect of the pineal in modulating the immune system and the connotation of “kidney corresponds with winter” through observing the level of golden hamster's interleukin-1 (IL-1)，IL-2，IL-6 and IgE and IgG in seasons after removing the pineal and comparing it with normal golden hamsters.Methods:Two-month-old Golden hamsters were divided into four groups：vernal equinox，summer solstice，autumn equinox and winter solstice.Each group was subdivided into experimental group (row pineal extirpation) and control group.Golden hamsters were fed until vernal equinox，summer solstice，autumnal equinox and winter solstice.Blood was drawn from abdominal aorta on these four days after 9:00 pm，and ELISA method was used to measure the relevant immune index.Results:The content of IL-2，IL-6，IgE and IgG had obvious seasonal rhythmicity.The content of IL-1，IL-2，IL-6 and IgG reached the lowest in winter.It was shown that the pineal could regulate the secretion of IL-2，IgE and IgG，and IL-2 lost the regularity of seasonal change after removing the pineal.Conclusion:The content of serum interleukin and immune globulin basically is high in spring and summer and low in autumn and winter，which coincides with the theory of “winter-storing” in traditional Chinese medicine.And the pineal can partly regulate the immune system.