Deep rock mass has theunique "self-stressed" block-hierarchical structure, in whichpendulum-type wave phenomenon is one of the typical dynamiccharacteristic phenomena, reflecting the incompatible anddiscontinuous dynamic properties of the deep block rock mass.Pendulum-type wave is a new type nonlinear and elastic reversalwave propagating with low frequency and low velocity, which isquite different from the longitudinal or transverse waves.Pendulum-type wave could lead to rock burst, bump of earthpressure and other severe geological hazards occurring in deeprock mass, and could not be well explained by the classicalcontinuum mechanics. In this paper, the state of arts of theexperimental and theoretical studies on pendulum-type waves inhome and abroad is firstly presented, and the main characteristicparameters of pendulum-type waves and their variation laws arethen summarized. Finally, the focusses and development trends inthe studies on pendulum-type waves are suggested.