Objective:　To　study　the　effects　of　different　parameters　(thickness,　orthodontic　displacement,　elastic　modulus)　from　Invisalign　on　canine　displacement　and　periodontal　ligament　(PDL)　stress　during　mandibular　canine　intrusion　treatment.　Methods:　Forty-eight　different　Invisalign　models　were　used　to　simulate　canine　intrusion　treatment　by　using　the　finite　element　method.　Results:　The　initial　displacement　of　the　canine　and　stress　on　canine　PDL　were　proportional　to　the　thickness,　intrusion　displacement,　and　elastic　modulus　of　the　Invisalign,　and　the　intrusion　displacement　had　the　greatest　influence　on　canine　displacement.　During　canine　intrusion　treatment,　the　compressive　stress　on　PDL　was　the　most　sensitive　and　changed　easily　with　the　change　of　parameters.　Conclusions:　The　canine　displacement　may　increase　with　the　thickness,　intrusion　displacement　and　elastic　modulus　of　Invisalign　increasing,　however,　the　stress　on　PDL　will　also　increase,　showing　the　largest　increasing　magnitude　in　compressive　stress　on　PDL　meanwhile.　Therefore,　to　accelerate　tooth　movement　in　Invisalign　treatment,　it　is　suggested　to　use　the　assisted　devices　or　some　other　measures　such　as　attachment,　supplement　of　bracket-wires　treatment,　or　implant　anchorage.　Copyright　©　2017　by　the　Editorial　Board　of　Journal　of　Medical　Biomechanics.