Background WHO states risk communication as the conversation of actual information, guidance, and thoughts between specialists and people fronting risks to their well-being, economic or social safety. As risk communication activities are complex and costly usually, evaluation assessment are the best approach to advance risk communication interventions. This study aims to evaluate the effectiveness of risk communication and the quality of health communication materials developed during the 2019 cholera outbreak at Addis Ababa, Ethiopia. Methods A community-based parallel mixed design was conducted from May to June 2020 at Addis Ababa. A total of 605 adults were selected randomly from Addis Ketema sub-city and ten purposely selected adults were interviewed for qualitative data. In addition eight health communication materials on cholera were randomly selected for evaluation. The quantitative data were analyzed using SPSS version 25. After audio recorded interviews transcribed verbatim and translated into English the qualitative data were entered into open code version 4.02 for analysis. And then the data were analyzed using thematic analysis. Result Respondents exposed for cholera related messages and outbreak information were 71.8% and 52.7% respectively. Respondents have moderate knowledge for cholera with (M = 14.72 and SD ±4.02) with (0–34) scale range. Both Television and radio spots were found as simple and easy to understand and printed health communication materials score low quality. Poor documentation, lack of data management system and less attention for risk communication activities were identified as a gaps in risk communication in the study settings. Conclusion this study revealed the positive effects of risk communication messages in increasing individuals’ knowledge. Even though the risk communication spots were found to be simple and easy to understand, the quality of printed materials was low and less attention was given for the risk-communication activities. Thus, strengthening the quality of risk communication and materials development process is very important to bring desired effects in disease prevention strategies and for effective emergency responses in the future.