IntroductionCatatonia arises from serious mental, medical, neurological or toxic conditions. The prevalence range depends on the setting and the range is anything from 7% to 63% in other countries. South African prevalence rates are currently unknown. The proposed study is a quantitative descriptive study using the Bush Francis Catatonia Screening Instrument as a screening tool with a data capturing information sheet to extract clinical information from patient folders. The study will investigate: (1) prevalence of catatonia, (2) clinical and demographic correlates associated with catatonia, (3) predictors of catatonia, (4) response to treatment and (5) subjective experience of catatonia.Methods and analysisThe setting is an acute mental health unit (MHU) within a regional, general medical hospital in Nelson Mandela Bay, South Africa, which accepts referrals from within the hospital and from outlying clinics. Participants will be recruited from inpatients in the MHU from beginning of September 2020 to end of August 2021. Most admissions are involuntarily, under the Mental Health Care Act of 2002 with an age range of 13 to over 65 years. Participants who screen positive for catatonia will be followed up after discharge for 3 months to measure outcomes. Primary outcomes will include the 12-month prevalence rate of catatonia, descriptive and other data on presentation and assessment of catatonia in the MHU. Secondary outcomes will include data on treatment response, participants’ report of their subjective experience of catatonia and predictors of catatonia. Descriptive statistics, multivariate binomial logistic regression and univariate analyses will be conducted to evaluate associations between catatonia and clinical or demographic data which could be predictors of catatonia. Survival analysis will be used to examine the time to recovery after diagnosis and initiation of treatment. The 95% CI will be used to demonstrate the precision of estimates. The level of significance will be p≤0.05.Ethics and disseminationThe study has received ethical approval from the Research and Ethics Committees of the Eastern Cape Department of Health, Walter Sisulu University and Nelson Mandela University. The results will be disseminated as follows: at various presentations and feedback sessions; as part of a PhD thesis in Psychology at Nelson Mandela University; and in a manuscript that will be submitted to a peer-reviewed journal.