This paper gives out a general object-oriented meta-meta model to model the meta-model of CIM and SCL in IEC 61970 and IEC 61850 respectively， along with the correspondent mapping methods. Representing the meta-meta model with a first order language based on predicate logic， the meta-model turns out to be the interpretation of that formal language. For each meta-model， by defining a correspondent first order language， the real model is also an interpretation of that language. The transformation rules are also formulas of a first order language which is based on the two meta-models. Since both models and transformation rules can be expressed in predicate logic， the process of model transformation is nothing more than the operation and deduction of predicate logic. At last， a framework for automatic model transformation which should take the transformation rules defined manually as inputs， is suggested.