Background　and　aims.　For　repairing　the　ear　malformation,　it　is　recommended　in　China　to　use　the　over　than　10-years-old　rib　cartilage.　However,　according　to　our　clinical　experience,　a　better　post-operation　effect　can　be　found　using　about　the　7-years-old　cartilage　for　the　operation.　To　shape　a　harvested　costal　cartilage　and　to　perform　it　on　the　transplant　site　depend　on　the　mechanical　properties　of　the　costal　cartilage.　Hence,　the　aim　of　this　study　is　to　investigate　the　age　and　gender-related　biomechanical　properties　of　the　human　costal　cartilage.　Methods.　Human　costal　cartilages　were　harvested　from　25　female　and　45　male　donors　of　5-25　years　old　after　auricular　reconstructive　surgery.　The　specimens　were　divided　into　six　groups:　children　(5-10　years),　adolescent　(11-17　years)　and　adult　(18-25　years),　respectively,　in　males　and　females.　Tensile　strength,　stress-strain　relationship,　stress　relaxation　and　creep　were　tested　by　using　a　material　testing　machine.　Findings.　The　biomechanical　properties　of　costal　cartilage　are　donor　age　and　gender　related.　The　children　group　has　the　highest　tensile　strengths　(P　＜　0.01)　in　both　male　and　female　groups.　The　male　group　relaxed　and　crept　more　than　that　of　the　female　group　in　all　three　age　groups　(P　＜　0.01).　Interpretation.　These　findings　provide　a　further　support　for　the　potential　age　acting　on　the　human　costal　cartilage.　The　adolescent　has　the　lowest　strength,　this　could　be　a　reason　that　compared　to　using　the　children　costal　cartilage,　the　bigger　distortion　happened　after　using　the　adolescent　costal　cartilage　in　the　auricular　reconstruction　operation.　(c)　2006　Elsevier　Ltd.　All　rights　reserved.