A　Wankel　engine　with　hydrogen　direct-injection　enrichment　is　recognized　as　an　attractive　method　to　enhance　combustion　efficiency.　In　this　paper,　on　the　basis　of　the　chemical　kinetic　mechanisms,　a　three-dimensional　simulation　model　was　established　and　validated　by　the　measured　results.　The　ignition　and　combustion　processes　in　a　gasoline　Wankel　engine　with　hydrogen　direct-injection　enrichment　were　implemented　for　numerical　simulation.　The　influence　of　twin-spark　timing　was　firstly　analyzed　by　synchronous　ignition.　Further　investigation　was　then　conducted　to　simulate　how　to　effect　the　combustion　by　asynchronous　ignition　based　on　the　favorable　synchronous　ignition　timing.　Results　showed　that,　the　average　flow　velocities　were　18.8,　20.7,　23.6,　and　25.4　m/s　for　the　spark　timings　(ST)　of　45,　35,　25,　and　15　degrees　CA　BTDC　respectively.　With　retarded　ST,　the　rich　equivalence　ratio　approached　to　twin-spark　plug　continually.　For　synchronous　ignition,　at　a　larger　advance　of　ST,　the　duration　between　the　timing　of　the　vortex　dissipation　and　ST　was　longer,　and　the　ignition　delay　was　more　prolonged.　As　the　ST　advanced,　the　combustion　rate　was　enhanced　with　the　increment　in　chamber　temperature,　the　reactants　(C8H18,　C7H16,　and　H-2)　consumption　and　intermediates　(H2O2,　OH,　and　CH2O)　generation　were　accelerated,　the　maximum　H2O2　and　CH2O　decreased　whereas　the　maximum　OH　increased,　and　nitrogen　oxides　(NOx)　and　carbon　monoxide　(CO)　increased　sequentially.　For　asynchronous　ignition,　the　accelerated　flame　front　was　in　accordance　with　the　rotating　direction　of　the　rotor　while　the　opposite　direction　was　inhibited　during　the　combustion　process.　An　earlier　ignition　of　leading-spark　plug　(L-plug)　or　trailing-spark　plug　(T-plug)　provided　the　higher　flame　speed　and　faster　H-2　consumption,　which　contributed　to　the　higher　in-cylinder　pressure,　combustion　temperature,　and　NO　and　CO　production.　The　preferable　ignition　and　combustion　characteristics　was　realized　when　the　L-plug　angle　was　25　degrees　CA　BTDC,　and　the　T-plug　angle　was　35　degrees　CA　BTDC.　Compared　with　the　favorable　synchronous　ignition　timing,　the　flame　propagation　and　H-2　consumption　were　expedited,　the　peak　pressure　increased　by　2.8%,　the　corresponding　crank　position　advanced　by　3　degrees　CA　and　there　was　no　increase　in　NOx　and　CO　generation.　Therefore,　it　was　recommended　in　engineering　applications　that　the　ST　of　T-plug　advanced　appropriately　while　the　ST　of　L-plug　remained　constant.