Student misbehaviors in the classroom both disrupt students' attention and affect negatively teaching and learning process. With the increase of online courses after Covid-19 pandemic, the type of student misbehaviors changed a lot. The aim of research was to examine student misbehaviors encountered during online courses, to identify the most common and disruptive student misbehaviors from teachers' perspective and to put forth teachers' suggestions about proper behaviors. The research was a phenomenological study. Data were gathered from 71 teachers teaching different courses and working at various levels. For data collection, a semi-structured interview form developed by the researchers was used. It was assessed through descriptive analysis. According to findings, a list containing 27 different student misbehaviors was generated. Results showed that the most common misbehaviors were indifference to course, not attending course, turning off webcam and slanging. The most disruptive misbehaviors were making noise, absenteeism, and distractibility. Findings revealed that teachers had some ideas to overcome these misbehaviors such as taking attendance, getting family support, encouraging students to turn on webcam, creating intrinsic motivation and organizing parent meetings. It can be concluded that some unwanted student behaviors can be seen during online courses; however, it can be overcome with the help of some precautions taken by teachers.