An elastic buffer circuit for adjusting the timing between a satellite communication system of a time division multi-access (TDMA) type and a ground communication system is provided with a stable oscillator for generating a first clock signal whose frequency is N (N is an integer not smaller than 2) times the received clock frequency, a clock generating circuit for generating a second clock signal by frequency-dividing the first clock signal by N and, at the same time, setting the phase of the second clock signal on the basis of a sync code detection signal, and a data memory circuit for temporarily storing data signals in accordance with the second clock signal.