Experiments of dense-phase pneumatic conveying of pulverized coal using nitrogen were performed in an experimental test facility with the conveying pressure up to 4MPa and the solid-gas ratio up to 500 kg/m3. The influences of the total conveying differential pressure, the moisture content, the superficial velocity and the pressure on the mass flow rate and the solid-gas ratio were investigated. Shannon entropy analysis of pressure fluctuation time series was developed to reveal the flow characteristics. Based on the distribution of the Shannon entropy in the different conditions, the flow stability and the evolutional tendency of Shannon entropy in different regimes and the regime transition processes were obtained. The results indicate that the solid gas ratio and Shannon entropy rise with increase in the total conveying differential pressure. A phase diagram and Shannon entropy reveal preferable regularity with superficial velocity. Shannon entropy is different for the different flow regimes, and it can be used to identify the flow regimes. As the moisture content increases, the mass flow rate, the pressure drop and Shannon entropy decrease. Shannon entropy rises with increase in pressure drop.