There has been an increase in the vulnerability in Internet security, and the unconscious usage of the Internet is a very important issue throughout the world as it is in Cyprus today. The best way to solve such an issue would be to make people aware of this situation. Based on this idea, teachers should firstly be trained to use the Internet in a safe and conscious manner so to be able to aid their students and the student's parents in the correct and safe usage of the Internet. The aim of this study is to determine teachers' self-efficacy and perceptions in safer use of the Internet so to be able to identify and develop a multidimensional tool, which is both valid and reliable, and can be therefore used in other scientific studies as well. Through a confirmatory factor analysis, the "Scale for the Self-Efficacy and Perceptions in the Safe Use of the Internet for Teachers" was validated in four dimensions: "Security in Social Networking Sites," "Malicious Software," "Web Security & Social Engineering" and "Computer Security," The scale developed has the characteristics of being the first of its kind in a developing country such as Cyprus. According to the results of the study, the scale in terms of validity and reliability was found to be appropriate in all aspects of the necessary criteria. As a result, the developed scale could help or be used by teachers, in Cyprus and in other countries, to be able to access the Internet safely and aid them in other scientific areas of study in determining teachers' self-efficacy.