Due　to　the　fact　that　the　exponential　function　expansion　nodal-SP3(EFEN-SP3)　method　needs　further　improvement　in　computational　efficiency　to　routinely　carry　out　PWR　whole　core　pin-by-pin　calculation,　the　coarse　mesh　acceleration　and　spatial　parallelization　were　investigated　in　this　paper.　The　coarse　mesh　acceleration　was　built　by　considering　discontinuity　factor　on　each　coarse　mesh　interface　and　preserving　neutron　balance　within　each　coarse　mesh　in　space,　angle　and　energy.　The　spatial　parallelization　based　on　MPI　was　implemented　by　guaranteeing　load　balancing　and　minimizing　communications　cost　to　fully　take　advantage　of　the　modern　computing　and　storage　abilities.　Numerical　results　based　on　a　commercial　nuclear　power　reactor　demonstrate　an　speedup　ratio　of　about　40　for　the　coarse　mesh　acceleration　and　a　parallel　efficiency　of　higher　than　60%　with　40　CPUs　for　the　spatial　parallelization.　With　these　two　improvements,　the　EFEN　code　can　complete　a　PWR　whole　core　pin-by-pin　calculation　with　289×289×218　meshes　and　4　energy　groups　within　100　s　by　using　48　CPUs　(2.40　GHz　frequency).