The twelve meridians, also known as the twelve regular meridians, are symmetrically distributed on both sides of the body. They form the main trunk of the meridian system and are the primary pathways for the circulation of qi (vital energy) and blood. These meridians are directly connected to the internal organs.

The pathways of the twelve meridians follow specific directions, either ascending or descending, and they interconnect to form a continuous, unending flow of qi and blood throughout the body. Besides being directly connected end-to-end, they also have branches that provide more comprehensive connections.

Traditionally, the twelve meridians are categorized as arm meridians, leg meridians, yin meridians, and yang meridians.

The order and arrangement of the twelve meridians result in specific ways of communication within the body. Traditional Chinese Medicine (TCM) uses Yin/Yang theory to distinguish and understand the pattern of meridian flow, which can be summarized as follows:

On the arm, the three yin meridians (along the inner side) run from the chest to the hand; the three yang meridians (along the outer side) run from the hand to the head.

On the leg, the three yang meridians (along the outer side) run from the head to the foot; the three yin meridians (along the inner side) run from the foot to the chest.

Each meridian passes through either the hand or foot, starts and ends at specific regions, connects to an internal organ, and runs along certain body parts.


Some specific patterns are formed:

Exterior-Interior Pairing: The meridians on the inner and outer sides of the limbs are paired as exterior and interior, which are connected on the hand or foot. For example, the Lung (1) and Large Intestine (2) meridians are paired. The other five pairs of meridians are Stomach (3) and Spleen (4), Heart (5) and Small Intestine (6), Bladder (7) and Kidney (8), Pericardium (9) and Triple Burner (10), and Gall Bladder (11) and Liver (12) meridians. This exterior-interior relationship is believed to strengthen the connection between the organs and meridians.

In acupuncture, this pairing is used to select points for treatment. For example, since the Lung and Large Intestine meridians are paired, they are closely related clinically. Lung problems can thus be treated by selecting points on the Large Intestine meridian in addition to points on the Lung meridian.

Same Name Pairing: The arm and leg meridians with the same yin/yang names are connected in the chest or head region, creating a direct link between the upper and lower body. For example, the Large Intestine Meridian (2, yang ming on the arm) runs to the head region, where its endpoint connects with the Stomach Meridian (3, yang ming on the leg), which starts there.

For diseases involving certain meridians, physicians will select points from meridians with the same yin/yang name for acupuncture and moxibustion treatment, which can yield more satisfactory results. For example, lung problems or diseases along the Lung Meridian (tai yin of the arm) can be treated by using points on its communication partner, the Spleen Meridian (tai yin of the leg), in addition to the points on the Lung Meridian.

Belonging and Connecting Pairing: Each of the twelve meridians is associated with one organ and connected to another organ. For example, the Tai Yin Lung Meridian (1) is paired with the Yang Ming Large Intestine Meridian (2); the Lung Meridian is associated with the lungs and connected with the large intestine. This relationship of “belonging” to one organ and “connecting” to another requires a pairing of yin and yang meridians, expressing a close connection between the yin organs and the yang organs.

Physiologically, the paired organs work closely, and in pathological conditions, they can influence each other. In acupuncture treatment, physicians often select points on the paired meridians to enhance the treatment of diseases in the corresponding organs.  

Six Yin Meridians



Six Yang Meridians

The Order and Arrangement of the 12 Regular Meridians