Background: In home care, eHealth implementation requires health care professionals and home care clients to change their behavior because they have to incorporate the use of eHealth into their daily routines. Knowledge of factors that influence the use of eHealth in home care is needed to optimize implementation strategies. However, a comprehensive overview of such factors is lacking. Objective: The aims of this study were to (1) provide insight into the types of eHealth that are used and preferred in home care and (2) identify factors that influence the use of eHealth in home care according to health care professionals and home care clients. Methods: A scoping review and online, cross-sectional survey were conducted sequentially. The survey was conducted among Dutch health care professionals with a nursing background who were working for a home care organization at the time. The capability, opportunity, motivation, behavior (COM-B) model, which posits that for any behavior (B) to occur, a person must have the capability (C), opportunity (O), and motivation (M) to perform the behavior, was used to identify influencing factors. The use of a theoretical model may contribute to a better understanding of how to achieve and sustain behavior change in clinical practice. Results: We included 30 studies in the scoping review. The most frequently studied type of eHealth was a telecommunication/telemonitoring system. The survey was completed by 102 participants. The most frequently used types of eHealth were electronic health records, social alarms, and online client portals. A health app was the most frequently preferred type of eHealth. We identified 22 factors that influence the use of eHealth in home care according to health care professionals and home care clients. Influencing factors were organized into the components of the COM-B model, namely capability (n=6), opportunity (n=10), and motivation (n=6). We found that there is no single influencing factor that is key to the complexity of eHealth implementation. Conclusions: Different types of eHealth are used, and many types of eHealth are preferred by health care professionals. The identified factors that influence the use of eHealth in home care relate to all components of the COM-B model. These factors need to be addressed and embedded in implementation strategies of eHealth to optimize the use of eHealth in home care.