Objective To explore the effect of warming-needle acupuncture at different time on the superoxide dismutase （SOD） and T cell subsets of old people to determine the best period of time of the day for the treatment to delay the aging. Methods Thirty cases were randomized into Chenshi group and Weishi group with 15 in each. Both groups were treated with warming-needle acupuncture at Guanyuan （CV 4） and Zusanli （ST 36） （both sides）. The Chenshi group was treated at 7:00 to 9:00

while the Weishi group treated at 13:00-15:00

once everyday

5 times as one course. Before treatment and after 4 courses of treatment

the contents of SOD and T cell subsets in the serum of the two groups were determined for comparison. Results After treatment

the SOD and the CD3+ and CD4 + contents of T cell subsets were significantly increased in both groups

CD4+/CD8+ of the Chenshi group was significantly increased （P<0.05 or P<0.01）

and the CD3+ and CD4 + contents and CD4+/CD8+ of the Chenshi group were increased more significant than those of the Weishi group （P<0.05 or P<0.01）. The D-value of SOD

CD3+ and CD4 + contents

and CD4+/CD8+ of the Chenshi group before and after treatment was bigger than that of the Weishi group （P<0.01）. Conclusion The warming-needle acupuncture in Chenshi is more effective on the SOD and T cell subsets of the aged people than in Weishi. The result of acupuncture given at Chenshi is better in anti-aging.