Objective To evaluate the rationality of drug treatment for cardiovascular diseases in aged people and the effects of evidence-based practice. Methods Descriptive study was conducted to compare the therapies for the patients suffering from cardiovascular diseases before and after evidence-based practice by investigating drug use during 1998-1999 (211 cases) and 2002-2003 (211 cases). Results Among antihypertensive drugs, the ACEIs and diuretics played a more important role than before. CCBs and ACEIs were still the most frequently used drugs, and drug combination was more common, comparing to that before evidence-based practice. Lipid lowering drugs and ACEIs were used more common in coronary heart disease. Quality of life of patients was more emphasized and combination use of anti-anxiety drugs was adopted. When treating heart failure, β-receptor blockers, aldadinc and ACEIs were more frequently used. Conclusions After evidence-based practice, drug use is much more based on evidence instead of experience and textbook. As a result, the rate of reaching ideal blood pressure is higher than before. The rate of rational drug use before and after evidence-based practice has increased from 42% to 78%, respectively.