Measuring instrument with stacked rapid assembly structure and assembly method of measuring instrument

The invention relates to the technical field of electrics. The invention discloses a measuring instrument with a stacked rapid assembly structure and an assembly method of the measuring instrument. The measuring instrument comprises an instrument shell, and a bottom circuit board, a middle circuit board, a supporting sleeve and a top circuit board are sequentially arranged in the instrument shell from back to front; a bottom circuit board positioning rib, a bottom circuit board horizontal direction limiting rib, a bottom circuit board vertical direction limiting rib, a bottom circuit board supporting rib, a middle circuit board limiting rib, a supporting sleeve limiting boss, a top layer circuit board limiting rib and a buckle groove are arranged in the instrument shell. A positioning hole is formed in the bottom circuit board; a horizontal limiting plane is arranged on the middle circuit board; and a top layer circuit board horizontal direction limiting plane is arranged on the top layer circuit board. Accor