Abstract: Objective: Using magnetic resonance imaging technology to observe the anatomical structures of Qihaishu acupoints and
measure the acupuncture depths to further clarify the anatomical levels, thus providing more accurate basis for clinical acupuncture
depths. Methods: The cross-sectional images of 36 adult volunteers´ Qihaishu acupoints were collected with a magnetic resonance
instrument, the anatomical levels were observed and analyzed, and the risk depths of straight piercing were tested. Results: The risk
depths of the right and left Qihaishu acupoints were（10.72±1.08）cm and（10.55±1.01）cm for males, and were（9.61±1.57）cm and
（9.56±1.52）cm for females. The risk depths were highly correlated with body builds. The risk depths of males were greater than those
of females, and the difference was statistically significant（P＜0.01）. Conclusion: Magnetic resonance sectional image can clarify the
anatomical structure of Qihaishu acupoints. On the basis of 0.8-1.0 inch straight piercing, the acupuncture depths can be adjusted
moderately according to body builds of the patients.

Key words: Qihaishu, acupoint, depth, anatomy, MRI