Tunable　diode　laser　absorption　spectroscopy　(TDLAS)　is　a　widely　used　diagnostic　technique　due　to　its　high　sensitivity,　fast　response,　low　cost,　and　other　merits.　Hydrocarbon　detection　is　a　field　of　great　interest　in　the　application　of　tunable　diode　lasers　as　hydrocarbons　are　fundamental　molecules　in　many　industrial　processes.　Many　tunable　diode　lasers　are　only　suitable　for　single　species　detection　due　to　the　short　scanning　range　and　in　real　situations.　However,　different　hydrocarbon　species　tend　to　exist　simultaneously.　Here　we　present　a　laser　system　based　on　the　difference-frequency　generation　(DFG)　method　for　simultaneous　hydrocarbon　mixtures　detection.　The　direct　absorption　spectra　of　different　hydrocarbons　covering　various　groups　(e.g.,　alkane,　olefin,　and　aromatic)　were　measured.　The　measurements　of　the　concentration　dependence　of　absorbance　for　each　molecule　were　carried　out.　The　R2　values　were　larger　than　0.997,　which　demonstrated　the　system　can　measure　hydrocarbons　covering　different　molecular　classes　accurately.　The　mixture　components　were　identified　using　the　independent　component　analysis　and　quantitative　analysis　was　performed　using　the　classical　least-squares　method.　Future　studies　will　focus　on　the　validation　of　the　system　in　actual　processes.　©　2021　Elsevier　B.V.