IntroductionPhysiotherapy can include both device-guided slow breathing and device-guided slow breathing in the treatment of systemic arterial hypertension. MethodsA systematic search of all published randomized controlled trials on the effects of device-guided and non-device-guided slow breathing on hypertensive patients, without language restriction, will be carried out until January 2020 in nine databases: Pubmed / MEDLINE (Medical Literature Analysis and Retrieval System Online), Latin American and Caribbean Health Sciences Literature (LILACS), EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Physiotherapy Evidence Database (PEDro), Cumulative Index to Nursing and Allied Health Literature ( CINAHL), Scopus, Web of Science, Livivo, as well as a search of clinical trial records databases, CT.GOV (Clinical trials.Gov), and bases for the Open Grey gray literature, Gray Literature Report, ProQuest Central (Citation, Abstract or Indexing and Dissertations and Theses). In all of these databases, potentially eligible studies including completed and ongoing ECAs were researched. The quality assessment of the included studies will be conducted using the Cochrane Risk of Bias Tool for Randomized Trials. The overall quality of the evidence for each outcome will be assessed using the Grading of Recommendations, Development and Evaluation (GRADE) system. DiscussionThis systematic review will provide a summary of the current evidence on the effects of both device-guided slow breathing and device-guided slow breathing on blood pressure levels. This information can contribute to decision making by health professionals related to the use of these interventions in hypertensive patients. Following the guidelines, this systematic review protocol was registered with the Prospective International Register of Systematic Reviews (PROSPERO) number CRD42020147554.