A cap for a MEMS package includes a main body having a bottom surface, a top surface, a plurality of accommodations recessed from the bottom surface towards the top surface, and a plurality of slots recessed from the top surface towards the bottom surface in a way that the top surface is defined into a plurality of regions corresponding to the accommodations respectively. After completion of the MEMS package, the package can be cut along the slots into a plurality of MEMS package units, such that the cutting work can be done quickly and the cutting burrs can be minimized.