A robust pitch synchronizer marking the pitch boundaries is reported. It is based on a modified version of matched filtering. The fundamental motive for the development of this algorithm is the observation that the voiced speech envelope resembles a distorted sawtooth train with fast rising and slowly-falling magnitudes. A matched filter with sawtooth impulse response of adjustable length is used to measure the peakedness feature of the pitch. Speech signal is first rectified and low-pass filtered before it is input to the matched filter. The filter output known as the measure function output achieves its peak value when the impulse response duration matches the pitch period of the waveform under investigation. The use of measure function in pitch boundary determination is completed by the use of the AMDF (average magnitude-difference- function) as a similarity measure. The combination of matched filtering measure function and the similarity measure of AMDF gives rise to a robust pitch synchronizer. It is demonstrated that the algorithm works well for noisy speech signal of up to 3 db signal-to-noise ratio.