Introduction: Our hospital faced an uphill battle with increasing clinical emergencies, a surge of patients, and compliance with the new regulations during the COVID-19 pandemic. Thereby, the code blue team developed a protected code blue protocol to minimize the infectious risk of the code team members and provide efficient management of emergencies during a lifesaving situation. Objectives: This project aimed to help the core team members to practice the new protected code blue protocol using in-situ simulation. The drills might improve the self-confidence of the code team members in performing their role, clear identification of themselves, effective communication skills, and teamwork. Methods: The mock code team developed different scenarios and ran the drills in 17 departments in different shifts within 8 weeks. A convenience sample of 269 staff participated in the drills. Participants included physicians, respiratory therapists, nurses, and other disciplinary staff. A debriefing was conducted to identify areas of improvement. Participants completed an evaluation form during the debriefing. The form included questions using a Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree) to rate the variables. Descriptive statistics and the Pearson correlation coefficient were used to test the hypotheses. Results: Out of the 269 participants, 125 staff completed and returned the evaluation form. The mean overall rating of the protected mock codes was 4.184 at a scale from 1 (very poor) to 5 (excellent) with a standard deviation of .827. The Pearson correlation coefficient ( r ) between the overall rating of the training and the amount of self-confidence in performing their role was .697 ( p =.000); clear identification of themselves was .329 ( p = .000); effective communication skills was .500 ( p = .000); and teamwork was .526 ( p = .000). Limitations: The project was conducted in a teaching hospital. The results might not apply to different care delivery settings. Conclusions: The findings of this project demonstrated that in-situ simulation improved the self-confidence of the code team members, communication skills, and teamwork in performing the protected code blue protocol for a COVID-19 suspected or confirmed patient with cardiac arrest.