学术论文中的关键词是指为了文献标引工作从报告、论文中选取出来的用以表示全文主题内容信息款目的单词或术语。

一篇论文关键词的数目一般是3至8个，最好是4-5个。例如：下面是一篇文章的关键词：

Key words:bridge engineering; concrete thin-wall box-shape structure; structural mechanics method; temperature stress

上述4个关键词都是词组或专业术语，而不是“单词”，所以英文关键词多为词组，一般不要将无实际意义的单词study, research, analysis, development, 等等作为关键词。例如：

Key words:deep; soft; rock; roadway under high stress; numerical simulation with FLAC3D; bolting combined support应修改为Key words:soft rock roadway under high stress; numerical simulation with FLAC3D; bolting combined support

Key words:shallow; coal; the seam; fully-mechanized face; the regularity be shown of the mining pressure; the numerical simulation应修改为Key words:shallow coal seam; fully-mechanized face; mine pressure behavior law; numerical simulation

Key words:college; students; mental; health; credit: system: study; suggestion应修改为Key words:college students; mental health; credit system

这里要特别强调一下，一般不要将冠词(the, a)放置在关键词的前面或中间，也就是说，一般在关键词中不可有冠词(the, a)。