The invention relates to a stacker crane which is especially suitable for automatically stacking fluid materials which are contained in bags. The stacker crane comprises a bag-direction guiding mechanism, a ranking and group organizing mechanism, a layering bag pushing mechanism and a pressing and exhausting mechanism all of which are located on an upper layer platform, comprises a vibration compaction mechanism, a stacking plate lifting mechanism, a tray bin, a tray output mechanism, a stacking plate output mechanism and an all-line electrical control system all of which are located on a lower layer platform, and comprises a climbing and conveying mechanism. The bag-direction guiding mechanism is used for automatically guiding products, the ranking and group organizing mechanism is used for automatically ranking and integrating the products, the layering bag pushing mechanism is used for integrating the products for the second time, and the pressing and exhausting mechanism is used for exhausting the air in the products for the second time. The vibration compaction mechanism is used for vibrating and compacting the products evenly, the stacking plate lifting mechanism is used for lifting stacking plates, the tray bin is used for storing trays, the tray output mechanism is used for automatically outputting the trays, the stacking plate output mechanism is used for automatically outputting the stacking plates, and the all-line electrical control system is used for controlling executive components. Under the premise that the stacker crane is suitable for conventional automatic stacking of ordinary materials, the stacker crane is more suitable for automatically stacking the fluid materials, safe and reliable, environment-friendly effects can be achieved, the stacking appearance is attractive and orderly, and full automation is achieved.