The purpose of this study is to identify the knowledge of CEIT student teachers on the information security. The study was conducted via survey method and profited from the third and fourth grade 375 CEIT student teachers at universities in Sakarya, Amasya, Erzincan and Siirt. The data was collected with the means of Information Security Knowledge Instrument. In the analyzing the data, frequency and percentage analyses were employed, and in determining whether the student teachers' knowledge of information security differs according to the various variables, Mann Whitney U test and Kruskall Wallis tests were applied. According to the results, it was identified that CEIT student teachers' knowledge level of information security is low. In addition, it was concluded that while CEIT student teachers' knowledge of information security differs according to gender and university, it doesn't change with learners' age, grade, period of computer ownership, daily computer and internet usage time, and taking any lecture on information security. Based on the results, it will be useful for student teachers' to go through a compulsory course in CEIT curriculum for the aim of receiving knowledge in information security.