AimTo examine the effectiveness of a pressure injury prevention program for private for‐profit nursing homes.DesignThis study was a two‐arm cluster randomized controlled trial. Ten private for‐profit nursing homes made up the clusters.MethodsThe participants were nursing home residents who aged 60 or above regardless of whether or not having pre‐existing pressure injuries and also three types of nursing home assistants who provided direct care to the residents from 10 private for‐profit nursing homes. These 10 nursing homes were randomly assigned to either the experimental or the control group. There were 477 and 536 resident participants and 51 and 62 nursing assistant participants in the experimental and control groups, respectively. The residents were the study participants and the nursing assistant participants were the interveners. The experimental group had the pressure injury prevention program implemented while the control group received the usual care. The primary study outcome which was the pressure injury incidence was analysed by GEE. Significance was set at a p‐value of ≤.05. The data were collected between September 2017–March 2018.ResultThere were significant interactive effects of time and group on the incidence of pressure injuries (p = .0015) and on the skill performance of the nursing assistant participants (p < .0001).ConclusionsAn evidence‐based pressure injury prevention program reduced the development of the pressure injuries and improved the skill performance of the nursing assistant participants. It is highly recommended that private for‐profit nursing homes with high proportion of non‐professional nursing assistants and insufficient nurses adopt this program for improving the prevention care of pressure injuries.ImpactThis research has an impact on prevention care of pressure injury in private for‐profit nursing homes with high proportion non‐professional nursing assistants which have the similar characteristics as the nursing homes studied in various regions and countries.Trial registration: The Controlled Trial registration ID is NCT02270385.