The aim of this study is the methodological evaluation of Clinical Practice Guidelines (CPG) in hypertension. This is the first in a series of review articles, analysis, assessment in methodology and content of clinical practice guidelines in Cardiology. Of all clinical practice guidelines, three were selected and the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument was used to assess each guide. The guidelines obtained the lowest score in the domain of applicability (mean 43.8%); while the highest score was for clarity of presentation (mean 81.5%). The lowest percentage was found in the applicability domain (European guideline) and the highest of all scores was found in two domains: scope and purpose, and clarity of presentation (Canadian guideline). Assessing the quality of the clinical practice guidelines analyzed, the Canadian is one with the best scores obtained by applying the AGREE II instrument, and it is advised to be used without modifications.