An auto-lift cable-free long-term observation apparatus for deep-sea bed pore-water pressure comprises a lower bit, a counterweight, a master control cabin, float material, an upper bit and a protective frame. An auto-lift pore pressure meter is controlled through a hydroacoustic/long-wave communicator and a marine controller. During deployment, a deploying support and the auto-lift pore pressure meter are sent to the surface of the sea bed through a hook; the lower bit starts drilling into sediment until a set depth; the hook is retracted through a cable, and deployment is complete. During recycling, a control signal is transmitted to start a releaser, the auto-lift pore pressure meter is separated except the lower bit and the counterweight, and the auto-lift pore pressure meter is enabled to float up and recycled. The apparatus has the advantages that repeatedly deploying and recycling the complex deep-sea instruments is avoided, work efficiency is improved, scientific research cost is lowered, and artificial disturbance to the field research environment caused in the recycling and re-deploying process is avoided.