The invention discloses a rigid-flexible combined
printed circuit board preparation method. The rigid-flexible combined
printed circuit board comprises a rigid sub board, a
dielectric layer, a flexible sub board, another
dielectric layer, and another rigid sub board which are laminated sequentially. The method comprises the following steps of: flexible board preparation, rigid board preparation,
dielectric layer preparation, pressing, cover opening, and post processes. In the invention, a PI
film resistance glue is pasted in a rigid board slot area; a flow type prepreg (a PP sheet) windowing area is increased; and the
total thickness of the PP sheet is controlled to be less than the
total thickness of a
polyimide cover film and a
polyimide resistance glue film, so that the flow type prepreg can be applied to preparation of the rigid-flexible combined
printed circuit board. The excessive glue length of the rigid-flexible connecting point of the pressed printed circuit board is less than 1.0mm, so that the requirements of the IPC-6013B relevant regulation are met.