Objective To formulate a scientific and reasonable evaluation model of post competency ,and to provide references for selection ,training and evaluation of orthodontic assistant specialist in china .Methods Items of competency for orthodontic as‐sistant specialist were established basing on semi structured interviewing and literature research ,and then Delphi technique was used to consult 22 orthodontic experts .The collected data was analyzed by SPSS 19 .0 .Results The positive coefficient for two round specialist survey was 95 .45% after two round specialist survey ,the authority coefficient was 0 .865 ,as well as the values of significant test for coordinate coefficient opinions were P<0 .01 .The evaluation competency model for orthodontic assistant special‐ist was consisted of entry requirements and evaluation system including 4primary indicators ,15secondary indicators .Conclusion The evaluation competency model is reliable and valid ,which can provide reference for selection ,training and evaluation of ortho‐dontic assistant specialist .