The purpose of this research was to investigate the relationship between teachers’ fear of missing out (FoMO) levels and their cyberloafing behaviour and to reveal whether teachers’ FoMO and their cyberloafing behaviour differ according to their gender. The sample of the research consisted of 702 secondary school teachers working in state schools within the borders of Istanbul in 2019-2020 education year. According to the research, it was identified that the level of teachers’ FoMO levels and cyberloafing behaviours were moderate. It was detected that teachers’ FoMO levels differed significantly according to gender. With this result, male teachers’ FoMO levels were higher than female teachers’ FoMO levels. Similarly, it was observed that there was a significant difference between teachers’ cyberloafing behaviour and gender. According to this result, it was found that male teachers’ mean score of cyberloafing behaviour was higher than female teachers’ mean score of cyberloafing behaviour in all sub-scales. In addition, a positive significant relationship between teachers’ FoMO and their cyberloafing behaviour was observed.