比例代表制（Proportional Representation，PR），是议会选举中分配议席的主要两种方法之一，另一则是多数制。

比例代表制以每一参选组别所得选票占全部的百分比分配议席，反映社会多元不同意见。此一方法最早出现于瑞士，并于欧洲大陆发扬光大。席次分配计算，可分为两类：最大余额法及最高均数法（如汉狄法）。

一般认为，比例代表制有利小党发展而且比较客观反映各政治组织的实力，但同时容易滋生激进情绪。因此不少国家议会各设政党得票门槛，德国国会及联邦州议会选举采取了全国得票数5％的政党门槛限制。

Proportional representation (PR) characterizes electoral systems by which divisions in an electorate are reflected proportionately in the elected body. If 30% of the electorate support a particular political party, then roughly 30% of seats will be won by that party. The essence of such systems is that all votes contribute to the result: not just a plurality, or a bare majority, of them. Proportional representation requires the use of multiple-member voting districts (also called super-districts); it is not possible using single-member districts alone.