Lidarisaneffectivetoolforremotelymonitoringtargetorobject,butthelidarsignalisoftenaffectedbyvariousnoisesorinterferences.Therefore,detectingtheweaksignalsburiedinnoisesisafundamentalandimportantprobleminthelidarsystems.Inthispaper,aneffectivenoisereductionmethodcombiningwaveletimprovedthresholdwithwaveletdomainspatialfiltrationispresentedtodenoisepulselidarsignalandisinvestigatedbydetectingthesimulatingpulselidarsignalsinnoise.Thesimulationresultsshowthatthismethodcaneffectivelyidentifytheedgeofsignalanddetecttheweaklidarsignalburiedinnoises.