Bevacizumab treatment is associated with an increased risk of hypertension (HTN), a potential marker for effectiveness. We aimed to assess whether grades 2-3 HTN during bevacizumab treatment was associated with increased overall survival (OS) or progression-free survival (PFS). One hundred and eighty-one patients with metastatic colorectal cancer (CRC), who were treated in our Department from January 2009-February 2011 were included. Bevacizumab was administered jointly with standard first- or second-line chemotherapy protocols. Blood pressure was measured before each treatment. HTN was graded using common toxicity criteria. There were 181 CRC patients. Grades 2-3 HTN developed in 81 patients (44.75 %) but not in 100 patients (55.25 %); no patient developed grades 4-5 HTN. Median follow-up was 15.2 months. HTN was associated with better OS in HTN-positive versus HTN-negative patients (median not reached vs. 36.8 months, p = 0.029) and better PFS (29.9 vs. 17.2 months, p = 0.024, respectively). Bevacizumab-related HTN may represent a biomarker for clinical benefit in metastatic colorectal cancer patients.