Objective:　to　investigate　the　role　of　associated　factors　in　the　effectiveness　of　laser　treatment　for　prolapsed　lumber　intervertebral　disc.　Method:　302　prolapsed　lumber　intervertebral　discs　in　212　patients　were　treated　with　percutaneous　laser　disc　decompression　(PLDD).　Patients　were　followed　up　by　12month,　the　associated　factors　which　affecting　the　effectiveness　of　treatment,　ie　age,　duration　of　illness　were　analyzed.　Results:　Punctual　Success　rate　was　100%.　After　12　month＇s　follow　up,　86%　successful　outcomes　were　obtained,　in　which　93%　successful　outcomes　were　obtained　in　patients　less　than　50　years　old,　92%　successful　outcomes　was　obtained　in　the　patients　whose　duration　of　illness　less　than　1　year.　2009　SPIE.