Polymerase chain reaction （PCR） has been applied in diagnosing amebic liver infection by detecting pathogenic Entamoeba histolytica DNA in liver aspirates. Oligonucleotide primers found to be specific for the gene encoding the 30 kDa molecule of this pathogenic ameba were used in the test. Liver aspirates obtained from 23 patients with amebic liver abscess substantiated by typical clinical manifastation or with very high titres of anti-E histolytica antibedies by ELISA were found to be positive by PCR. Fourteen control samples （3 cases of bacterial liver abscess

I of liver cancer and 10 of other abscess） were all found to be negative to this reaction- The results suggested PCR to be a specific and sensitive tool for diagnosing amebic liver abscess infections.