The Internet is, an indispensable platform for the provision of products and services of a company and for the communication with customers (Hsu et al. 2013) . A significant increase in the number of e-commerce interfaces in the Business-to-Business (B2B) environment has been already been noticed since for several years (Pohl 2018). One of the biggest challenges facing small and medium-sized enterprises (SME) in the construction industry is the complex issue of retaining customers in a B2B business relationships (Forooz Pishgar et al. 2013). Especially in an internet-based, constantly changing context, this is an uncertain and ambitious challenge (Pitta et al. 2006). In our study, we investigate the antecedents of customer loyalty of B2B-customers on using the iInternet . Based on the findings of Janita et al. (Janita and Miranda 2013), we developed a conceptual model containing the nine constructs potentially influencing loyalty of B2B-customers in the internet. Conducting an online survey with the B2B customers os WERUB2B customers of WERU, a German industrial component manufacturer in the building sector, our final data set contains 187 observations. Results show a direct, highly significant effect of "trust" and "customer satisfaction" and a highly significant total effect of "image" on "customer loyalty".