The purpose of this study is to investigate the comprehensibility of the text of the literature review section in research articles over the last 30 years. In other words, this study aims to investigate the trend of the change of LR text readability from 1988 to 2018. In this study, readability is defined as the level of difficulty of understanding a text based on the style of writing. This study follows previous studies to use the Flesch Reading Ease for measuring readability of the literature review section of research articles from 1988 to 2018. The literature review section of each selected research article was copied to a word file and their readability index of each was determined using the Flesch Reading Ease of the three distinct periods over the last 30 years. Results indicated an increase in the difficulty level of the text of the LR section over the last 30 years. Results also revealed a significant difference in the difficulty of the three distinct areas of research articles. Readability is generally considered one of the most important characteristics of effective writing. Yet little is known about the readability of the literature review section of academic articles in different journals. It is suggested that more research be conducted on the topic to shed more light on the stated gap.