我國政黨對公職候選人之提名以初選作為機制者，主要為中國國民黨與民主進步黨，目前兩黨均採取黨員投票與民意調查兩階段的初選方式，此種初選制度的設計，有其互補的效果，對於弱化不當動員、強化人口結構代表性、貼近中間選民及減少負面策略性投票等甚有效益。不過，兩黨對於黨員投票與民意調查設有不同的比例，使得兩階段初選呈現不對稱的現象，此一現象衍生出對政黨發展、新人被提名、搭配現行選制等諸多互斥的效應。本文由兩黨初選制度中兩階段不同比例的設定切入，探討現行兩階段初選所存在的問題，並提出建議，作為兩黨改革初選的另一思考。

　　　　　KMT and DPP are the major parties to adopt primary as the system of nomination in this country. Both party all take the two-stage primary, closed primary and poll, to be the system of nomination. The designation of this kind of primary has its effect to supplement each other between the two-stage primary, such as weakening the mobilization abused, enhancing the representative sample, diminishing the negative strategic voting, and approaching the median voter. But KMT and DPP specified different ratio in each stage, and that makes the two-stage primary come out to the phenomenon of asymmetry. This phenomenon causes some problems, such as the problem of development of party, the problem of emergence of novice, the problem of match of the existing system of election, etc. Therefore this article will explore the arrangement of ratio between the two-stage primary, and to infer the problem of the existing primary, and then to provide the suggestion of reform as the other consideration to the primary.