Electronic commerce represents the way in which companies sell goods and services via the Internet. The past few years have seen an expansion in the world of business technology and as a result, many companies from various industries have started implementing technology to create a competitive advantage in the business environment. Such a way of doing business enables companies to reach a larger number of consumers on a wider market. In doing so, companies can sell goods and services on national and international markets using their own website, and in addition, sales can take place continuously regardless of the business hours of the company's physical store. The subject of the thesis research is electronic commerce in the business of companies within the construction sector, on the example of the company Bačelić d.o.o. The aim of this work was to determine and analyze the quality of the application of electronic commerce in the construction sector and to determine the determinants and importance of electronic commerce in business, as well as to empirically evaluate the satisfaction with the quality of the electronic commerce of the observed company on a sample of selected customers who simultaneously buy construction products via electronic commerce in several companies. The paper showed that slightly more than half of the respondents still prefer going to a physical store, taking into account that this way they create a close relationship with the seller, but also that in this way they can easily get help. websites before buying products in a physical store, and respondents are generally satisfied with the offer and the way the company's web shop functions. However, it was noticed that progress is needed in some segments of the business, for example, adding information for certain items to the web shop or providing the option of paying for products by cash on delivery.