1-Pentene is the main composition of alkene in practical gasolines. Laminar flame speeds of 1-pentene/air were measured in a constant volume combustion bomb at initial pressures of 0.1 MPa and 0.3 MPa, initial temperatures of 350 K and 450 K, and equivalence ratios ranging from 0.5 to 1.6. A new chemical model including 83 species and 560 reactions was developed by reaction pathway analysis for mechanism reduction and core mechanism combination based on the available detail models, which can be better predicted laminar flame speed and ignition delay time in all tested conditions. Sensitivity analyses indicate that the laminar flame speed of 1-pentene/air mixtures mainly results from the thermal effect at different initial temperature, and the chemical effect at various equivalence ratios. The analyses also show that the initial pressure affects the relative contribution of the H and OH radicals to the laminar flame propagation of 1-pentene and the effect becomes smaller between H and OH radicals with the increase of equivalence ratio.