Abstract: SPME method was widely applied to analysis of the ignitable liquids in fire debris. An improved approach on SPME was considered as an expansion of SPME sampling from common thermal desorption mode to solvent-based desorption mode for the analysis of ignitable liquids from fire debris. 30 μL CS₂ to yield a test sample was amenable to GC/MS analysis by injection. Compared with thermal desorption this approach retained the advantages of sampling time and non-solvent， while simultaneously improved the sample utilization and the method flexibility. The optimized experiment conditions for solvent-based desorption were determined.