The company's marketing and marketing policies greatly strengthen the company's position on the global market by bringing final products and services closer to final consumers. Today, the Internet is used as a cheap method of advertising and analyzing consumer behavior due to its indispensable role in the everyday life of a person. It is precisely for this reason that today an increasing number of research focuses on consumer behavior on the Internet and the way in which the Internet participates in shaping it. Understanding consumer behavior is important for gaining a strategic advantage over competitive companies in today's markets, which are faced with the challenges of high competition, the impact of globalization, inflation, the consequences of the COVID-19 pandemic and the overall geopolitical situation in the world. Communication with consumers no longer requires physical contact, and the use of the Internet allows companies to get in touch with a larger number of people. This has changed the way services and products are sold and presented to customers. Traditional marketing methods must be adapted in order for companies to survive in the new environment. Consumer behavior research is interdisciplinary and brings together numerous experts from the fields of economics, ICT, psychology and sociology to answer current questions. This graduate thesis will present an overview of the literature on the formation of consumer behavior on the Internet and will investigate the impact of the COVID-19 pandemic on changes in consumer behavior on the Internet in Croatia.