Objective:To investigate the analgesic and anti-inflammatory effects of Indigo Naturalis by different administrations.Method: Two administration ways（ig and external application）were applied respectively for 4 days.The experimental animals were randomly divided into different groups:blank control group

positive control group and Indigo Naturalis therapy groups（150

300

600 mg·kg-1 by ig;400 mg for a mice and 500 mg for a rat by external application）.Analgesic effects of Indigo Naturalis were investigated by hot plate test and acetic acid writhing test in mice;anti-inflammatory effects of Indigo Naturalis were investigated by xylene-induced aruical swelling in mice and granuloma induced by cotton ball implantation in rats.Result: By ig

Indigo Naturalis decresed the pain threshold in mice caused by hot plate test to 47% and acetic acid writhing test to 40%

shown a strong difference

compared with blank control group（P<0.05

P<0.01）.The inhibition rate of aruical swelling was 48% on the acute inflammation model

shown a striking anti-inflammatory effect

compared with blank control group（P<0.05）;but there was no great effect on the sub-acute inflammation model.By external application

Indigo Naturalis had a good analgesic effect to the pain in mice caused by hot plate（P<0.01）

but did not had a good effect in the acetic acid writhing test.However

it showed good effects on both acute and subacute inflammation models（P<0.01）.Conclusion: The results show that Indigo Naturalis have certain analgesic and anti-inflammatory effects by different administrations.But there are several differences in the analgesic and anti-inflammatory effects due to the different ways of administration.