The honeycomb sealswere widely applied in turbomachinery industries due to theirexcellent rotordynamic and controlling leakage performance. Stateof the art on the discharge behavior, heat transfer androtordynamic characteristics of honeycomb seal was reviewed basedon the experimental tests, numerical simulations and theoreticalanalysis. Firstly, the leakage flow characteristics of thehoneycomb seal and corresponding sealing mechanisms wereintroduced. The fluid-heat conjugate of discharge and totaltemperature increase, including heat transfer performance of thehoneycomb seal was illustrated. The fluid-structure interactionmechanisms due to unsteady leakage flow excitation androtordynamic characteristics of honeycomb seal was summarized.Finally, the research and development of honeycomb seals foradvanced turbomachinery design technology were briefly presented.