The invention relates to the field of film attaching for electronic components, in particular to a film cutter unit and an automatic cutting, transferring and fine-positioning machine for intracavity molding of mesh. The machine comprises an X-directional sliding table, an X-directional translation mechanism, a first Y-directional sliding table, a first Y-directional translational mechanism, a film cutter holder, a film cutter, a second Y-directional sliding table, a second Y-directional translational mechanism and a mesh sucker block. The first Y-directional sliding table is slidably connected to the X-directional sliding table. A Y-directional slider is fixedly connected to the first Y-directional sliding table. The film cutter is provided with a guide slot and a circular cutting edge. The second Y-directional sliding table is slidably connected to the first Y-directional sliding table. The mesh sucker block is fixedly connected to the second Y-directional sliding table. One end of the mesh sucker block penetrates the guide slot of the film cutter and is provided with suction holes which are connected to a vacuum generator. By the use of the film cutter unit, the problem that traditional manual operation is time consuming and labor consuming is solved; operating efficiency is high; the machine is applicable to simultaneous cutting of multiple films; the cut film can be fixedly attached to the end of the mesh sucker block; the film can be attached to an accurate position.