A multimeter with filtered measurement mode is disclosed. The multimeter includes a signal conditioning circuit, a low-pass filter, a microprocessor, a measurement circuit, a root-mean-square (RMS) converter, a display unit, and an external rotary switch. The signal conditioning circuit receives a control signal to select an operation mode of the multimeter. The low-pass filter is electrically connected to the signal conditioning circuit. The microprocessor is electrically connected to the signal conditioning circuit. The measurement circuit is electrically connected to the microprocessor and the RMS converter to measure a signal outputted from the RMS converter. The display unit is electrically connected to the microprocessor and the measurement circuit. Also, the external rotary switch is optionally connected to the microprocessor. Whereby rotating the external rotary switch to generate the control signal and perform a low-pass filtering mode to communicate the low-pass filter with the RMS converter.