The invention provides a multi-link planar tuning component, and an assembly clamp and an assembly method therefor. Tuning mechanisms of a plurality of cavities are integrated into a whole, so that the structure complexity is reduced; the welding success rate is improved; and the structure compactness and miniaturization of a whole klystron are ensured. The multi-link planar tuning component employing a component form is small in size and compact in structure; reliability detection is carried out before the multi-link planar tuning component is welded to the klystron; the welding reliability of the multi-link planar tuning component is higher than that of a multi-film structure; the multi-link planar tuning component has advantages for the klystron which works at a high frequency; the problem of a welding difficulty caused by a small space is solved; by an half-open mold design form, the multi-link planar tuning component is convenient to install and dismantle; and the deformation when films are taken out is reduced.