A speech synthesizer includes sampled speech signal latch at the first signal input terminal to process signal read from the input terminal and output latched sampled speech signal, and features its speech synthesizing circuit at the second signal input terminal and sampled speech signal one to process the operational signal from the second signal terminal and apply self-voltage to input of sampled speech signal latch to repeatedly input same sampled speech signal several times for speech operation and output synthetic signal. The frequency of operational signals is higher than read signal and the frequencies of speech synthesizing circuit and read signals are in same period.