The first phytoplankton bloom in the Northern Adriatic Sea appeared in the 19th century and the expressed interest in the study of this phenomenon has increased since the eighties of the previous century. During this period, the intensity of the bloom intensified and became a significant ecological and environmental problem, affecting marine life, local economies and human health. This process, primarily caused by eutrophication due to agricultural runoff and urban wastewater discharge, results in the proliferation and increase in biomass of various types of algae. The unique hydrological features of the Northern Adriatic, characterized by shallow waters, limited water exchange and significant intake of nutrients from rivers, especially the Po River, worsen the frequency and intensity of these blooms. Climate changes, meteorological conditions and human impact additionally affect the dynamics of blooming. This review examines the mechanisms of algal blooms, their ecological impacts and socioeconomic consequences in the northern part of the Adriatic Sea. It also emphasizes the importance of monitoring, developing predictive models and management strategies aimed at mitigating the adverse effects of blooms, which are a key element for the preservation of the marine ecosystem of the Northern Adriatic Sea and the protection of public health.