Acupoint is the basis of acu

puncture. To elaborate the theory of acupuncture

the structure and function of acupoint should be clarified in advance. By exploring the discussion upon the classification

distribution and structure of acupoint in

Huangdi Neijing

(

Inner Canon of Yellow Emperor

)

qi zheng lun

(on meridian points and extra points)

jie jiao lun

(on convergence of joints) and

guan ji lun

(on three-dimensional structure of acupoint) are extracted. Based on whether located on the fixed sites

acupoints are classified into meridian points and extra points

while the meridian points are divided into 4 categories

i.e

maishu

gukong

qixue

and

muxue

. The convergence of joints illustrates the principal rule of acupoint distribution. The density of the major and key acupoints is proportional to the size and the complexity of function of joints. Acupoint is recognized as a three-dimensional structure in consideration of its external distribution on the body surface and the substances inside the body

which can be explored and examined. In addition

the relationship between meridian points and extra points

the significance of meridian points in different conditions

and the approaches to acupoint study are deeply discussed and analyzed. The crucial problems and the way for solving them are proposed for the future study to provide the references to the inheritance and innovation of acupuncture.