Introduction: Knowing about arterial hypertension could favor adherence to treatment for better control of blood pressure. Objective: To evaluate the association between hypertension awareness and adherence to treatment in hypertensive patients at Hospital Nacional Edgardo Rebagliati Martins in Lima, Perú. Materials and methods: An analytical cross-sectional study was performed, including a convenience sampling of 340 hypertensive patients from cardiology clinics, during the period May-August 2015. The main variable was awareness of hypertension, which was measured using the hypertension awareness questionnaire (CSH, by its acronym in Spanish); the response variable obtained corresponds to the degree of adherence to the treatment, which was measured through the Martin-Bayarre-Grau (MBG) questionnaire. The Poisson regression was used to calculate prevalence ratios (PR) with 95% confidence intervals and a p value of <0.05 to establish statistical significance. Results: There is an association between low awareness of hypertension and partial adherence to treatment (PR=1.4, 95% CI: 1.2-1.8), a history of more than 10 years of hypertension (PR=0.7, 95% CI 0.6-0.9), not receiving enough information on hypertension (PR=1.4, 95% CI: 1.2-1.7) and consultation time longer than 15 minutes (PR=0.5, 95% CI: 0.3-0.7). Conclusion: Patients with low knowledge on hypertension are more likely to have partial adherence to treatment.