Objective To analyze the clinical characteristics and the treatment of 20 confirmed A/H1N1 flu cases of serious conditions. Methods The 20 confirmed A/H1N1 flu cases of serious conditions were collected and we analyzed their Clinical characteristics, treatment and prognosis. Results The 20 cases of serious conditions were given Oseltamivir, endotrachealintubation, ventilator ventilator assistant, high dose intravenous injection of Gamma-globulin/ albuminum/plasam of A/H1N1 flu rehabilitation, appropriate liquid recovery and hypothermic treatment, etc. A total of 19 of 20 confirmed A/H1N1 flu cases of serious conditions were cured and 1 case died. Conclusion The intent observation, early detection and early intervention are very helpful for A/H1N1 flu cases of serious conditions.