Fluorescence　immune-chromatography　is　a　kind　of　immunoassay　which　is　widely　used　in　quantitative　detection　area.　However,　the　background　baseline　drift　with　relatively　large　amplitude　during　test　is　a　huge　problem　for　the　overall　performance　of　the　quantitative　detection　system,　and　the　existing　background　baseline　recognition　and　adjustment　methods　were　based　on　online　or　offline　data　processing,　which　brings　huge　computational　burden.　To　solve　this　problem,　this　paper　proposed　a　background　baseline　recognition　and　adjustment　method　from　the　aspect　of　optical　design.　It　integrated　background　acquisition,　conditioning　and　control　functions　which　could　adjust　the　photo-electric　signal　of　the　background　in　real　time　until　the　sampling　value　of　background　baseline　was　within　the　threshold.　Finally,　the　peak　value　of　the　test　strip　was　detected.　To　examine　the　performance　of　the　system,　ten　standard　test　strips　with　different　concentrations　were　selected　for　background　baseline　detection.　Besides,　linearity　and　coefficient　of　variation　(CV)　of　the　system　was　also　calculated.　Results　showed　that　the　fluctuation　range　of　baseline　was　within±4%　of　the　threshold,　whereas　the　CV　of　the　test　strip　background　was　2.57%.　Furthermore,　although　the　occupancy　rate　of　background　amplitude　for　A/D　unit　was　decreased　from　31.7%　to　2.4%,　CV　of　the　system　was　still　lower　than　3%,　which　indicates　that　the　system　has　much　wider　detection　range　than　other　congeneric　detection　devices.　©　2016　Croatian　Society　MIPRO.