The invention relates to an irregular multi-degree of freedom docking device and a working method, in particular to a multi-degree of freedom docking device which is used for docking all types of vehicle engines with gearboxes on the military armored vehicle assembly line, and a working method of the docking device, and belongs to the field of automatic control. The irregular multi-degree of freedom docking device comprises an irregular multi-degree of freedom motion platform, a control system, a monitoring system and a control handle, wherein the irregular multi-degree of freedom motion platform is composed of three pairs of different types of cylinders, upper platforms, lower platforms and hooke joints, and mainly used for implementing six degrees of freedom motions. By applying the system, one person can control the motion platform to adjust the positions and angles of the gearboxes, to dock the engines with the gearboxes, convenience and quickness are realized, the labor costs can be greatly reduced, precision is high and reliability is high.