Firms are the main users of e-public procurement applications (hereinafter e-procurement), so their acceptance to adopt this technology is a crucial element in its successful implementation. Nonetheless, very few studies have focused on this subject. This article aims to identify and analyse the factors affecting private companies’ adoption of e-procurement. Relying on several solid theories in the field of acceptance and adoption of innovation, namely the Technology Acceptance Model (TAM), the Diffusion of Innovation theory (DOI), the Technology, Organization, Environment framework (TOE) and the Iacovou et al. model, we constructed a research model that included the most important potential factors that can influence this variable. Our model was tested according to the survey method. Based on the data received from 760 Belgian firms spread over a wide range of economic activities, we identified five main variables that could explain about 33.5 % of the total variability of...