Background: Nurses have an important role in the process of providing information and helping patients prepare for and receive bad news and understand and cope with the bad news they have been given. This study was conducted to evaluate the effect of communication skills training on the level of skill and participation of nurses in breaking bad news. Materials and Methods: This semiexperimental study was performed on 60 nurses working in educational hospitals of Birjand, Iran in 2019. Convenience sampling was performed and the participants were randomly assigned to the two groups of intervention and control. For the experimental group, an integrated workshop on communication skills was held. Before and after the intervention, the Setting, Patient Perception, Invitation, Knowledge, Empathy, and Strategy (SPIKES) SPIKES questionnaire (breaking bad news skills) and the questionnaire of participation in breaking bad news were completed. The collected data were analyzed using descriptive and inferential statistics (independent t-test) in SPSS software. Results: The mean (SD) of breaking bad news skills after the intervention was 57.42 (10.13) in the control group and 65.12 (5.68) in the experimental group and the between-group difference was statistically significant (t59,41 = 3.93, p < 0.001). After the intervention, the mean (SD) of nurses' participation in delivering bad news was 21.17 (5.21) in the control group and 25.77 (4.96) in the experimental group and the between-group difference was statistically significant (t75,48 = 3.94, p < 0.001). Conclusions: It seems that to increase the ability of nurses in the process of breaking bad news, it is necessary to teach them communication skills.