The　presence　of　the　uncertainties　introduced　in　the　fabrication　processes　lead　to　inherent　randomness　in　physical　dimensions　of　microwave　components.　As　such,　it　is　of　particular　importance　to　perform　statistical　analysis　and　yield　optimization　before　putting　a　component　into　production.　As　electromagnetic　(EM)-based　adjoint　sensitivity　techniques　have　become　commercially　available　these　years,　it　is　possible　to　perform　direct　yield　optimization　using　full-wave　EM　simulators.　However,　the　requirement　of　intensive　simulations　to　cover　the　entire　statistic　of　possible　outcomes　makes　direct　yield　optimization　computationally　prohibitive.　In　this　paper,　we　propose　to　apply　parallel　computation,　which　is　a　powerful　tool　to　speed　up　full-wave　EM　simulations,　to　yield　optimization　of　microwave　components.　With　parallel　computation　technique,　the　total　yield　optimization　time　is　significantly　reduced　compared　with　the　conventional　sequential　yield　optimization　method.　The　proposed　technique　is　demonstrated　by　a　four-pole　waveguide　filter.