Atmospheric　pollution　is　a　critical　issue　in　public　health　systems.　The　simulation　of　atmospheric　pollution　dispersion　in　urban　blocks,　using　CFD,　faces　several　challenges,　including　the　complexity　and　inefficiency　of　existing　CFD　software,　time-consuming　construction　of　CFD　urban　block　geometry,　and　limited　visualization　and　analysis　capabilities　of　simulation　outputs.　To　address　these　challenges,　we　have　developed　a　prototype　system　that　couples　3DGIS　and　CFD　for　simulating,　visualizing,　and　analyzing　atmospheric　pollution　dispersion.　Specifically,　a　parallel　algorithm　for　coordinate　transformation　was　designed,　and　the　relevant　commands　were　encapsulated　to　automate　the　construction　of　geometry　and　meshing　required　for　CFD　simulations　of　urban　blocks.　Additionally,　the　Fluent-based　command　flow　was　parameterized　and　encapsulated,　enabling　the　automatic　generation　of　model　calculation　command　flow　files　to　simulate　atmospheric　pollution　dispersion.　Moreover,　multi-angle　spatial　partitioning　and　spatiotemporal　multidimensional　visualization　analysis　were　introduced　to　achieve　an　intuitive　expression　and　analysis　of　CFD　simulation　results.　The　result　shows　that　the　constructed　geometry　is　correct,　and　the　mesh　quality　meets　requirements　with　all　values　above　0.45.　CPU　and　GPU　parallel　algorithms　are　13.3×　and　25×　faster　than　serial.　Furthermore,　our　case　study　demonstrates　the　developed　system’s　effectiveness　in　simulating,　visualizing,　and　analyzing　atmospheric　pollution　dispersion　in　urban　blocks.　©　2023　by　the　authors.