This study aimed to study the vaccination status among Coronavirus disease 2019 (COVID-19)-positive cases admitted in isolation centers in Sudan. This is an analytical, cross-sectional, hospital-based study. It was conducted in isolation centers from January to June 2022. An organized, structured, and pretested questionnaire was used in this study (n = 297). The majority of the study participants were aged more than 60 years (71%), most of the study participants were males (58.7%), and the majority of the participants were residents in rural areas (52.7%). Most participants had COVID-19 symptoms for 1 to 2 weeks (81.7%), and only 7 (2.3%) were vaccinated. This study found that those vaccinated were more likely to be improved and discharged. In addition, this study found that lack of oxygen and mechanical ventilation was associated with deaths. Vaccination is considered an important tool to reduce the risk of many infectious diseases. The current study found that vaccination against COVID-19 is effective and can reduce the risk of COVID-19 infection. Based on that, more people should consider taking the vaccine.