Effects　of　the　hydrogen　blending　ratio,　equivalence　ratio　and　compressed　pressure　on　the　ignition　delay　time　of　DME/H2/O2/N2　mixture　are　investigated　using　a　rapid　compression　machine　(RCM)　at　compressed　temperature　of　650~830　K,　compressed　pressure　of　1.94~2.45　MPa,　equivalence　ratio　of　0.83~1.25　and　nitrogen　dilution　ratio　of　89.74%　in　this　study.　Kinetics　model　was　built　to　predict　the　ignition　delay　time　and　simulate　the　combustion　process.　The　results　show　that:　with　the　increasing　hydrogen　blending　ratio,　there　is　only　little　change　about　the　first　stage　ignition　delay　time　of　DME/H2/O2/N2　mixture,　and　the　total　ignition　delay　time　extends;　with　the　increasing　equivalence　ratio　and　compressed　pressure,　the　first　stage　ignition　delay　time　of　the　DME/H2/O2/N2　mixture　only　has　little　change,　and　the　total　ignition　delay　time　shortens.　©　2016,　Science　Press.　All　right　reserved.