The location of organs and tissues at the tip of acupuncture needle inserted in acupuncture points was studied on the human transverse sections.<br>A female, japanese, cadaver (139cm long, and 52kg in weight) was fixed with an aldehyde mixture and frozen for 3 weeks at -30°C. Then the cadaver was cut into blocks along the transverse planes perpendicular to the median plane at each point of Bladder meridian.<br>This report describes the depth of organs and tissues in 5 transverse planes from DAITSUI (Governor vessel meridian) to KETSUINYU (Bladder meridian).<br>At DAITSUI, acupuncture needle penetrates through 7.5mm thick skin, 28.5mm thick hypodermis, and reaches to the transverse process of the 7th cervical vertebra at 36mm away from the surface. At DAIJO, the needle penetrates through the skin, hypodermis, trapezius, rhomboideus, and deep back muscles of 6, 8, 5.5, 10 and 14mm in thickness respectively. The needle reaches to the 2nd rib at 43.5mm away from the surface. At FUMON, the needle penetrates through the skin, hypodermis, trapezius rhomboideus, deep back muscles of 7, 5, 3.5, 4 and 18.5mm in thickness respectively. The needle reaches to the 3rd rib at 38mm away from the surface. At HAIYU, the needle penetrates the skin, hypodermis, trapezius, and deep back muscles of 6, 4, 3 and 22mm in thickness respectively, and reaches to the 4th rib at 35mm away from the surface. At KETSUINYU, the needle penetrates the skin, hypodermis, trapezius, and deep back muscles of 5, 3, 4 and 21mm in thickness respectively, and reaches to the 5th rib at 33mm away from the surface.<br>The depth of acupuncture points studies was discussed from the clinical points of view.