The invention belongs to the field of aero-engine external pipeline design, and particularly relates to a pipeline connecting device with multidirectional displacement compensation capability. The pipeline connecting device comprises a first pipeline, wherein one end of the first pipeline is a columnar port, the outer wall is an outer cylindrical surface, and the tail end protrudes to form a flange; a second pipeline, wherein one end of the second pipeline is a spherical port; and a connecting pipe which comprises a first sleeve opening and a second sleeve opening, wherein the first sleeve opening sleeves the first pipeline, an elastic O-shaped ring is arranged between the first sleeve opening and the outer cylindrical surface, the second sleeve opening sleeves the second pipeline, the position, corresponding to the spherical port of the second pipeline, of the second sleeve opening is in a horn shape, and a first connecting piece and the connecting pipe are matched in shape to clamp the elastic O- shaped ring. Through the integrated design of axial compensation and angular compensation, the compensation requirements of the pipeline in all directions can be met while the sealing performance is guaranteed; and the pipeline connecting device has the advantages of a simple structure, small occupied space and strong compensation capability.