Optical　tracking　systems　are　widely　adopted　in　surgical　navigation.　An　optical　tracking　system　is　designed　based　on　the　principle　of　stereo　vision　with　high-precision　and　low　cost.　This　system　uses　optical　infrared　LEDs　that　are　installed　on　the　surgical　instrument　as　markers　and　a　near-infrared　filter　is　added　in　front　of　the　Bumblebee2　stereo　camera　lens　to　eliminate　the　interference　of　ambient　light.　The　algorithm　based　on　the　region　growing　method　is　designed　and　used　for　the　marker＇s　pixel　coordinates＇　extraction.　In　this　algorithm,　the　singular　points　are　eliminated　and　the　gray　centroid　method　is　applied　to　solve　the　pixel　coordinate　of　the　marker＇s　center.　Then,　the　marker＇s　matching　algorithm　is　adopted　and　three-dimensional　coordinates＇　reconstruction　is　applied　to　derive　the　coordinates　of　the　surgical　instrument　tip　in　the　world　coordinate　system.　In　the　simulation,　the　stability,　accuracy,　rotation　tests,　and　the　tracking　angle　and　area　range　were　carried　out　for　a　typical　surgical　instrument　and　the　miniature　surgical　instrument.　The　simulation　results　show　that　the　proposed　optical　tracking　system　has　high　accuracy　and　stability.　It　can　meet　the　requirements　of　surgical　navigation.　(C)　The　Authors.　Published　by　SPIE　under　a　Creative　Commons　Attribution　3.0　Unported　License.　Distribution　or　reproduction　of　this　work　in　whole　or　in　part　requires　full　attribution　of　the　original　publication,　including　its　DOI.