The method on profile-control of micro-optic element in photoresist was presented.The difference between fabrication of binary optic element and that of continuous-relief MOE may not be ignored.A reciprocal equation among the depth,exposure,density of the developer and its etching time was inferred,with the appropriate conditions that proved to be useful for the MOE fabrications.The property and treatment of the photoresist were modified in order to meet the conditions of the reciprocal equation.As the result,some MOEs having accurate depth and good surface performance,with the evaluation of a typical element,were shown.