It has been more than three years since the emergence of the COVID-19 at the end of 2019. The COVID-19 epidemic has had a certain impact on human’s normal production and life, and it is also constantly changing people’s social cognition, which are reflected in the vocabulary. There are many new words invented and the words with a sudden increase in frequency appeared. This paper selects the important Chinese words related to the COVID-19 epidemic from 2019 to 2022 as the research objects, and divides these words into three categories: COVID-19 cognition, government measures and social life. By sorting out the meanings and usages of the words, this paper analyzes and explores the development trend of Chinese social cognition reflected by these words according to the timeline. The research found that these words reflect the gradual concretization of disease names caused by the COVID-19, the proliferation of the names of mutated virus, the sudden high frequency of related words, the strong generalization and creativity of words in specific fields, lots of related words come out in the era of intelligence and so on, as well as the spiritual thoughts and cultural cognition of Chinese people contained in the vocabulary.