The invention relates to a CAN bus sampling point testing method and device. The method comprises the following steps: configuring CAN interface equipment through CANoe of a PC-side; configuring a CANinterferer through CANStress of the PC-side; collecting a CAN bus message and sending a simulation message through the CAN interface equipment, wherein the CAN interface equipment collects the message existing on the CAN bus at every moment and transmits the collected message information to the PC-side, and the PC-side displays the bus message information through a Trace interface of the CANoe; performing interference through the CANStress to change the dominant level at a designated location of a RTR bit of the simulation message as the recessive level, thereby obtaining the testing data; and computing a sampling point location through the testing data. The accuracy rate and stability of testing the sampling point can be obviously improved, the testing environment is simple, and the operation is easy, and the method is suitable for the standard CAN or the extended CAN.