To study the effect of altitude hypoxia on γ-aminobutyric acid(GABA) content in the rat hypothalamus, A rapid method was established. content was determined by 6300 gold system high performance amino acid analyzer. under altitude hypoxia,the content of GABA in hypothalamus increased significantly. Analytical time was 8.87min which was 65.96min shorter than with the original one. The better repeatability (CV:1.39%) and recovery rate (98.81%) were observed.