An EMI-resistant circuit board assembly includes a plurality of circuit boards arranged in a stack and a metal shielding frame respectively sandwiched in between each two adjacent circuit boards. One of the circuit boards has at least one high-speed device producing high-frequency noises to the ambient, which result in EMI effect. The metal shielding frame is electrically connected to the ground potential of the circuit boards and shields the high-speed device on the circuit board to guide the high-frequency noises to the ground potential.