The aim of this research is to examine the speed of reading the uppercase and lowercase texts of primary school students. This research is the survey of quantitative research methods. The survey population of the research is the primary school students who are educated in the primary schools in the Sorgun district of Yozgat province. Cluster sampling used for sampling. The sample primary school students' number is 732. As a means of collecting data, a text was used from the textbook. The data were collected in three primary schools in the Sorgun district of Yozgat province in March 2018. The number of words a pupil reads in a minute is noted. Reading speed of text written with lower case letters is more than reading speed of text written with capital letters at all grade levels. The scores varied for the capital letters and lower case letters. At an alpha of 0.05, the analysis indicated a statistically significant difference among reading rate of the capital letters and lower case letters, (t=23.13, p<0.01), effect size 0.28 SD. The speed of reading lowercase letters text is 13% higher than the speed of reading capital letters character text. The text with lower case letter reading aloud score significantly higher mean scores than text with capital letter reading aloud score (?=0.278; F= 92,536; p<0.001; ?2=0.70. Secondary school students' reading aloud text with lower case letter score significantly higher than primary school students' aloud reading speed text with capital letters (p<0.001). Suggestions were made within the scope of the research results.