Available data for plagio-amphibolites in Chaozhuang Group from east- ern Hebei Province are examined. All these rocks occur in layer intercala- ted either with metasediments or with gneisses. In AEM diagram the plagio amphibolites mainly belong to calc-alkaline series and showed a higher con- tent of potassium. All rare-meth elements patterns are fractionated with slight enrichment in light rare-earth elements, (Ce/Yb)。ratios range from 1.1 to 4.4. The rare-earth elements patterns observed here are quite similar to those of calc-alkaline basalts and continental basalts. These imply that the occurrence of plagio amphibolite from Chaozhuang Group may be rala- ted to underplating beneath the Archaean continental crust.