新闻偏见是新闻客观性研究的重要组成部分，但国内学者在这方面的研究较少。作者通过谷歌学术选取了2000-2013年间的二十九篇美国的实证研究论文，以反映美国学术界在新闻偏见和倾向方面的研究现状。尽管对新闻偏见的研究范围涵盖多个学科和领域，政治仍然是学者们最为关注的话题；有约三分之一的文献中的研究是建立在与政治选举相关的各项数据和样本基础上的。本文还从新闻偏见的来源、表现与测量及影响三个方面概括了美国学者的研究结论。不论是在研究角度的多样性方面还是对数据信息的处理方面，这些实证研究都能为我国的新闻传播研究和实践提供有益借鉴。此外，明确美国媒体对内报道时对资本主义市场经济规律的臣服，以及在国际新闻报道中对美国价值观的维护，还可以帮助我们更全面地理解西方的新闻客观性。

News bias is an important aspect of news objectivity, but Chinese scholars have rarely researched upon it. In this paper, the author selected 29 positivist research papers by US scholars through Google Scholar search engine to examine news bias and slant literature in the US. Although researches on news bias can be found in many disciplines and fields, politics is still the dominant area scholars are concerned with, with about 1/3 of the papers based on data and sample collected about political elections. This paper also summarizes research findings on news bias in the US in terms of the source, presence and measurement, as well as effects of bias. These studies, their research methodologies and results all can serve as valuable reference for Chinese scholars in similar researches. The market-oriented news production rules in domestic reporting and pro-American stands of US media in international news reporting can also help Chinese journalists and scholars make a better understanding of western news objectivity.