Abstract: A pre-interpretation and execution method of Java computer program language is disclosed. In an embedded type device, a pointer lookup table is built for mapping a running code of each bytecode to a respective subroutine. When the embedded type device downloads a Java program from a network, the received running code is converted into the pointer data of the respective subroutine entrance point according to the pointer lookup table. The operator is converted from a network format into a machine format. An adjusting step is performed for maintaining a correction of corresponding addressing. The converted result is stored into the embedded type device. A pointer data representing a respective subroutine and the operator of machine format are read sequentially for being executed, so as to complete an execution of the Java computer program language.