An　innovative,　portable　fluorescence　reader　was　developed　for　the　determination　of　C-reactive　protein　based　on　a　lateral　flow　immunoassay.　The　C-reactive　protein　concentration　was　proportional　to　the　intensity　of　the　test　line　which　was　calibrated　relative　to　the　control　line.　To　quantify　the　fluorescence　intensity　of　the　lateral　flow　strip,　a　custom　illumination　module,　which　concentrated　the　excitation　beam　from　an　ultraviolet　light-emitting　diode,　was　developed　for　strip　scanning.　Accordingly,　a　high　sensitive　photodiode　with　a　preamplifier　was　chosen　as　the　detector　for　fluorescence.　For　good　repeatability,　the　strip　scanning　resolution　was　set　to　5　mu　m　between　data　points　by　controlling　a　linear　stage　actuated　by　a　stepper　motor.　Four　double-logistic　calibration　models　were　compared.　The　sensitivity　for　C-reactive　protein　was　0.1mg/L　and　the　linear　dynamic　range　extended　to　400mg/L.　The　optical　reader　provides　a　new　and　simple　approach　for　the　determination　of　C-reactive　protein　and　may　be　modified　for　other　similar　biomarkers.