Abstract: An on-line pressure measurement system was installed for a trickle-bed reactor with 10cm in diameter,the sampling speed was as fast as 686 times/sec which can fulfill the requirement of the practical need.With its help, the pressure pulsations of the three typical flow regimes existing in the bed which are trickling flow,transition flow and pulsing flow were measured.The pressure pulsation data were anaiyzcd by histogram and spectral density.