To disseminate evidence-based practice (EBP) among hospital-based health professionals, since 2007 the National Health Research Institutes (NHRI) of Taiwan has run a complex outreach program that includes information resource support and promotional campaigns. The aim is to evaluate the impact of this outreach program on the diffusion of EBP. Sixty-one regional hospitals in Taiwan. A cross-sectional, pre- and post-survey of a nationally representative sample of physicians and nurses was carried out in 2007 and 2009 to examine views related to EBP including changes in beliefs, attitudes, knowledge, skills, perceived barriers and behaviors. Physicians and nurses in the 2009 survey tended to have more knowledge and skill of EBP than their counterparts in the 2007 survey. They were less likely, however, to believe that EBP can improve patient care quality and to support the implementation of EBP. The prevalence of perceived barriers to EBP declined during the 2-year study period. In addition, physicians and nurses were more likely to access the online evidence retrieval databases according to the 2009 survey when compared with responses to the 2007 survey. The knowledge of, skill in, and behavior regarding EBP have improved among physicians and nurses of regional hospitals in Taiwan after a promotion period of 2 years and they perceive fewer barriers to EBP. These data suggest that the multifaceted nationwide promotion program of the type conducted by NHRI succeeded in diffusion and implementation of EBP among professionals.