The back-shu point of the Sea of Qi. Qihaishu (BL-24) sits in the lumbar region and works quietly but powerfully — tonifying the Kidneys, warming the lower back, and supporting the body's deepest reserve of Qi when it runs low.
Contraindications
As with all back-shu points in the lumbar region, keep to the recommended depth and needle perpendicularly. No special contraindications are noted for this point in the sources.
Name & story
The name 气海俞 Qihaishu means "Back Transport of the Sea of Qi" — and every word counts. Qi is the vital energy that animates the body. Hai means "sea" — a vast, deep reservoir. And Shu tells us this is a back transport point, a doorway on the back that opens directly into the organ it serves. The Sea of Qi it refers to is Qihai (Ren-6), the front point on the abdomen considered the body's great ocean of Qi. Qihaishu is, in a sense, its partner on the back — the rear entrance to that same ocean. When the ocean runs dry and the body's Qi is depleted, this point helps refill it.
Point family & character
Qihaishu (BL-24) belongs to the Bladder Meridian (BL), which runs the full length of the back carrying the back-shu transport points of all the major organs. BL-24 lies between Shenshu (BL-23), the great back-shu of the Kidneys, and Dachangshu (BL-25), the back-shu of the Large Intestine — a location that speaks to its role connecting Kidney Qi with the lower body and intestines.
Five-element dynamics
In Chinese medicine the lower back is the domain of the Kidneys, the root of all Yin and Yang in the body and the storehouse of Jing — the deep constitutional essence. Qihaishu sits right in this territory, at the third lumbar vertebra, flanked by the Kidney point and the Large Intestine point. It draws on the Kidney's warming Yang to support the lower back and the lower abdomen, and it helps move and regulate Qi in the region. When Kidney Yang is insufficient, the lower back grows cold and weak; when Qi is stagnant, pain and discomfort follow. Qihaishu addresses both.
Location
Find the third lumbar vertebra (L3) — it sits just below the level of the iliac crest, which is a handy landmark. From the lower edge of its spinous process, measure 1.5 Cun outward to either side. That is Qihaishu, level with BL-23 above and BL-25 below, all spaced one vertebra apart.
Anatomy & fascia
The point lies in the lumbar region, over the erector spinae muscles, 1.5 Cun lateral to the lower edge of the third lumbar vertebra (L3).
Needling
The needle is inserted perpendicularly (straight in). A sensation of heaviness or warmth spreading into the lower back or lower abdomen is typical.
Safe depth
Safe depth — 0.8–1.2 Cun.
Moxa, cupping & Tui Na
Moxa is particularly well suited here, especially when there is Cold, Yang Deficiency or chronic weakness in the lower back. Warming the point with a moxa stick or moxa cone brings gentle heat deep into the lumbar region and supports the Kidney Yang. Cupping and Tui Na massage along the Bladder Meridian in the lower back are also commonly used alongside this point for musculoskeletal complaints.
Functions
Tonifies Kidney Qi and warms Kidney Yang; Strengthens and warms the lower back; Regulates and moves Qi in the lower abdomen; Supports the Qi of the intestines and assists in regulating bowel function.
Indications
Lower back pain, stiffness and weakness in the lumbar region — especially when the pain is dull, chronic and worsened by cold or tiredness. Disorders of the lower abdomen related to Qi Deficiency or Qi Stagnation. Digestive and intestinal disturbances including constipation, diarrhoea and bloating. Urogenital weakness and dysuria. General fatigue and depletion of the body's Qi reserves.
Mind & spirit (Shen)
When the body's Qi is depleted to the point where a person feels not just physically exhausted but hollowed out — lacking will, lacking drive, lacking the basic energy to engage with life — Qihaishu quietly supports the reservoir that feeds everything. The Kidneys in Chinese medicine are the home of Zhi, the will and the capacity for determination. A well-supported Sea of Qi gives back not only warmth to the back and strength to the limbs, but also the steadiness and groundedness that allow the mind and spirit to feel secure.
Point combinations
With BL-23 (Shenshu) — to strengthen the Kidneys and warm and support the lower back. With Ren-6 (Qihai) — its front counterpart, together they form a front-and-back pair that powerfully tonifies the body's Qi reserve. With BL-25 (Dachangshu) — to regulate the lower intestine and address constipation or diarrhoea with lower back involvement.
Clinical spotlight
Qihaishu is one of those points that rewards careful attention in cases of chronic lower back pain with an underlying pattern of Qi Deficiency or Kidney Yang Deficiency — situations where the pain is not dramatic but persistent, where the patient feels worn down rather than acutely injured. Its position between the great Kidney point (BL-23) and the Large Intestine point (BL-25) makes it useful in combined lower back and bowel presentations, a pattern seen more often than one might expect in clinical practice. The pairing of Qihaishu (BL-24) on the back with Qihai (Ren-6) on the abdomen is a classic front-back combination for rebuilding depleted Qi.
The golden tip
For lower back fatigue and weakness, gentle self-massage of the lumbar region — running the thumbs or knuckles along both sides of the spine — will naturally pass over Qihaishu. A warm heat pack placed over the lower back, covering the area around L3, is a simple and effective way to warm the point at home, particularly comforting on cold days or when the back feels tired and heavy. Regular rest and warmth of the lower back are the basic self-care principles this point represents.
For education only — not medical advice. Consult a qualified practitioner.