HIV/AIDS patients in high prevalence areas with different routes of infection (sexually transmitted 878 cases, 527 cases of intravenous drug user, paid blood donor 652 cases) were choosen for traditional Chinese medicine (TCM) syndrome investigation for one-year clinical follow-up. This paper primarily concluded the nature, location and pathogenesis of AIDS diseases. Deficiency of Yang and Yin, combining deficiency of Qi are the basic deficiency syndromes, while stagnation of dampness, toxic fire are the excess syndromes; the disease location of HIV infector is spleen, main syndrome is deficiency of spleen Qi; the disease location of AIDS patient is kidney, main syndrome is deficiency of spleen and kidney Yang. The pathogenic development tendency is from deficiency of Qi to combining stagnation of dampness and toxic fire, finally to deficiency of Qi and Yin, deficiency of Yang.