The main purpose of this research was to do a confirmatory factor analysis of cyberbullying behaviors among undergraduate students in higher education institutions in northeastern Thailand. The sample included 1,062 1st-4th years bachelor's degree students in the academic year 2022 from five higher education institutions located in the Northeast of Thailand. Multi-stage sampling was employed. The research instrument was a constructed measurement form of cyberbullying behaviors of undergraduate students in institutions in the Northeast of Thailand. It was a 5-rating scale form with 30 items, each of which had a discrimination of 0.21-0.67 and a reliability of 0.99 by means of Cronbach's alpha coefficient. The findings from the confirmatory factor analysis revealed that the cyberbullying behavior model of the students in higher education institutions in northeastern Thailand consisted of five components; 1) Impersonation, 2) Intimidation and cursing others, 3) Disclose other people's private information, 4) Gossip or defamation of others, and 5) Deleting or blocking others from the group. The cyberbullying behavior model was consistent with the empirical data (Chi-square X[superscript 2] = 1.37, df = 2, p = 0.50, GFI = 1.00, AGFI = 1.00, CFI = 1.00, RMSEA = 0.00, SRMR = 0.00). This indicates that the model confirms the components of cyberbullying behaviors of undergraduate students.