For understanding of the role of monoamines in cerebral ischemia, 3-methoxy-4-hydroxyphenylglycol (MHPG), hydroxyindoleacetic acid (5HIAA) homovanillic acid (HVA) the three major monoamine metabolites in CSF of 33 patients and 18 controls were measured with high-performance liquid chromatography. Results showed MHPG was more sensitive to cerebral ischemia than the two others. All three metabolites were elevated in patients with severe ischemia but only MHPG and 5-HIAA were significantly elevated. A positive correlation between any two of metabolites was found in controls and in patients in the first week after stroke but altered at the end of the second week. Computer assisted multivariate analysis indicated 5-HIAA might contribute more to the state of illness in the acute stage while HVA the least. Clinically, MHPG appeared to be the most significant element on reflecting the degree of the damage and the prognosis of the disease among the metabolites.