Background: Undergraduate dental students are more susceptible to situations of stress that affected quality of sleep, such profiles of stress may result in sleep bruxism and/or awake bruxism, parafunctions that can affect oral and general health. The aim of the study was to evaluate the association of sleep bruxism, awake bruxism and sleep quality among dental students. Materials and methods: A cross-sectional study was performed including 260 Iraqi dental students from university of Baghdad aged from 20to25years old. Students enrolled in the third and fifth class participated in the study. The Pittsburgh Sleep Questionnaire Index (PSQI) was used for data collection. The PSQI was distributed during lecture classes. Sleep bruxism and awake bruxism diagnosis was based on self-reported data. Results: prevalence of sleep bruxism was 9.62% and prevalence of awake bruxism was 15.76%. Statistically significant differences were observed between students who had awake bruxism and the mean of PSQI global score and its components of sleep categories: PSQI global score and day time dysfunction (p<0.001), habitual sleep efficiency (p=0.044; p<0.05) and sleep quality (p=0.046; p<0.05). While for students had sleep bruxism the statistically significant differences were observed in sleep disturbance (p=0.021; p<0.05) and sleep duration (p=0.042; p<0.05). Conclusion: Poor sleep quality was an important factor among dental students, who reported awake bruxism as well as among those who presented sleep bruxism.