A system and a method for stack-caching method frames are disclosed, which utilize FSO (Frame Size Overflow) flag to control the execution mode of the processor. When FSO flag is set, it indicates that the method frame of the next method is larger than the limit value of a stack cache so that the method frame is placed to a memory stack. When FSO flag is cleared, it indicates that the method frame of the next method is smaller than the limit value of the stack cache so that the method frame is placed into the cache stack.