Objective To study the influence of decocting times and instrument on the quality of decoction.Methods Taking the effective ingredients of five formulas as the indices to compare the decocting rate of the effective ingredients in the decoction of high temperature and high pressure decoction machine and clay pot in different decocting times.Results The decocting rate of two-time decocting of the decoction machine was 47.1%～65.9% higher than that of one-time decocting.Compared with the decocting rate of two-time decocting of clay pot

the decocting rate of one-time decocting and two-time decocting of decoction machine was 63.5%～92.1%

111.1%～137.5% of clay pot respectively.Compared with the decocting rate of two-time decocting of clay pot

there was significant difference in the decocting rate of one-time decocting and two-time decocting of decoction machine（P<0.05 or P<0.01）.Conclusion The decocting rate of one-time decocting of decoction machine is slightly lower than that of the two-time decocting of clay pot

but the decocting rate of two-time decocting is higher than that of clay pot.Therefore two-time decocting with decoction machine is better on getting more effective ingredients.