This systematic review provides a high-quality, comprehensive summary of recommendations on hypertension (HT) and type 2 diabetes mellitus (T2DM), accentuating patient blood pressure, HbA1c levels, patterns of drug treatment, management, and screening of these diseases. The overall objective of the review is to support adapting existing clinical practice guidelines in Indonesia, Vietnam, and Myanmar. The database PubMed and the web search engines Google and Google Scholar were searched from October to December 2019 for evidence-based guidelines covering the overall disease management in Europe, the United States of America, and low and middle-income countries (Indonesia, Vietnam, and Myanmar—IVM later on). Nine studies were selected for the review, seven concerning HT and five T2DM. Guidelines in IVM and Europe identified HT as increased blood pressure (BP; ≥140/90 mmHg). IVM guidelines also recommended commencing drug treatment if lifestyle interventions were not successful. Four international HT guidelines recommended monitoring BP every few months, and the other three guidelines gave recommendations based on the patient’s current BP levels. All five T2DM guidelines recommended target HbA1c levels below 7%–6.5%, but only IVM guidelines included re-examination every 3–6 months. Metformin was recommended as the first choice of medical treatment, if not contraindicated. Amid the guidelines’ recommendations, there were no major variations in the Class of recommendation and Level of evidence (except IVM guidelines where COR and LOE were missing). Revision and completion of IVM guidelines by this grading system would enhance evidence-based and informed decisions in clinical care.