Objective: The bio-active contribution of main herb pairs in Xiangfu Siwu decoction (XFSWD) was evaluated by using the forward-reverse biological activity test. Method: Four animal models

including hot-plate test

acetic acid-induced writhing

dysmenorrheal mice model

and blood-deficiency mice model

were adopted to test the effect of every sample on different models. Result: In the three pain models

Rhizoma Cyperi-Rhizoma Corydalis (RCRC)have great analgesic effect. When RCRC are removed from XFSWD

its analgesic activities was lowered

even disappeared. While the analgesic effect of Rhizoma Cyperi-Angelicae Sinensis Radix (RCASR) was weaken than RCRC;and when RCASR was removed from XFSWD

the effect was not diminished clearly

some were even increased. In comparison with the model group

the amount of white blood cells

the weight of spleen and thymus of all samples had no significant difference in the blood deficiency experiment. Based on the number variation of red blood cells and hemoglobin

RCASR had strong blood-enriching function

while XFSWD and XFSWD removed RCASR showed no apparent effect. Further research showed that XFSWD could raise NO level and SOD activity

degrade Ca2+ level in the uterus of dysmenorrheal mice. Conclusion: In XFSWD

the blood-enriching effect of RCASR is very weak

RCRC plays important role in its analgesia effect. The inhibiting dysmenorrhea of XFSWD may be resulted from affecting the level of NO and Ca2+

and SOD activity. The forward-reverse bio-activity evaluation is an effectual method for studying on the compatibility regularity of traditional Chinese medicine formulae.